Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) Using UV/FeCl₃ in Industrial Soil

Round 1

Reviewer 1 Report (Previous Reviewer 1)

Comments and Suggestions for Authors

The reviewer has provided clear responses to the reviewer questions and reviewed the manuscript two times on June 5 and 28 2025, and the authors did not improve the manuscript and made it even more complicated, especially the introduction section. The fundamental questions remain unanswered and unaddressed. 

Reviewer Comments (3rd time) 

The introduction effectively highlights the environmental and health hazards posed by polycyclic aromatic hydrocarbons (PAHs) and touches upon Fenton-like reactions and conventional solvent extraction. However, it overlooks a broader discussion of established photocatalytic strategies for pollution mitigation from a catalyst-centric perspective. Various metals (e.g., Pt, Au, Ag) and metal oxides such as TiO₂, Cu₂O, FeP, and CeO₂ exhibit unique properties that enable highly efficient photocatalytic degradation of pollutants. Factors such as plasmonic effects, dielectric Mie resonances, clustering, shape- and size-dependent charge-carrier dynamics, and recombination pathways critically influence photocatalytic performance and can decouple thermal contributions from true photochemical activity. A concise discussion of these phenomena, along with other sensitization mechanisms, would provide readers with a holistic view of alternative photocatalytic technologies, highlighting the advantages of advanced nanostructured materials in environmental remediation. Please improve the introduction and consider answering all reviewer comments clearly to the point and detailed as needed. Thank you. 

Previous Ccomments 

Author's Notes

Reviewer 1

Previous comments

The paper entitled “Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic
Hydrocarbons (PAHs) Using UV/FeCl3 in Industrial Soil” is a novel work. This study investigates
using Fenton reagent (FeCl3/H2O2) for degrading polycyclic aromatic hydrocarbons (PAHs) in
contaminated soil. Higher concentrations of FeCl3 and H2O2 resulted in faster degradation of
PAHs, likely due to increased hydroxyl radical generation. This approach has the potential to
remediate PAH-contaminated soil quickly and effectively. The present manuscript in its present
form has minor corrections that includes captions errors and a few scientific shortcomings that
needs to be addressed carefully. The manuscript in the present form also has some grammatical
errors and also scientific shortcomings that needs to be addressed significantly and revise the
manuscript. For instance:
1. This research work utilizes a specific UV wavelength (306 nm). Can the authors comment
on the choice of this wavelength? Are there alternative UV wavelengths that might be more
efficient for PAH degradation, considering factors like penetration depth in soil?

There have been many studies which tested the affect of different UV wavelengths on the degradation of PAHs i.e. 250-700 nm, however we choose this wavelength because maximum studies gave best results at wavelengths of 250-350 nm and this specific UV wavelength was best suited under our experimental set up.

Moreover the use of light energy depends on the type of catalyst use. For example TiO2 perform only in ultraviolet rays in the solar spectrum owing to wide band gap energy and using certain materials like doping agents can help in extension of optical absorbing response from UV to visible wavelengths. In this regard few lines explaining the use of different light sources is added in the introduction section

Page 2, line no 49-56

2. 
   The authors investigated decontamination in industrial soil. How does the effectiveness of
   the treatment change depending on the soil composition (e.g., clay content, organic matter
   content)?

Studies relevant to the affect of UV radiation on PAHs decomposition and how soil properties affect its performance are now incorporated in the introduction section.  The text is colored as red page no 4, line no 167-175

3. 
   This impactful research explores the impact of FeCl3/H2O2 and UV light on PAH
   degradation, did the authors perform any control experiments performed without the
   catalyst or UV irradiation to isolate their individual contributions and can the authors
   comment on the degradation mechanisms and electron transfer scheme for the degradation
   of pollutants with schematic diagram, as this work would garner more interest in the
   broader readership of this journal?

Yes this work has explored the impact of UV radiation without catalysts or oxidizing agent. That treatment was given the name of control and is presented in table 1. Whereas the treatments with various concentrations of FeCl3 and H2O2 are presented in table no 2 (page 6 ) and 3 (page 7).

4. 
   This research contribution suggests a synergistic effect between FeCl3/H2O2 and UV light.
   Can the authors quantify this synergy by comparing the degradation rates achieved with
   the combined treatment compared to individual treatments (Fenton reagent alone or UV
   light alone)?

Yes the results of each treatment is discussed in details, moreover studies are added in discussion section which outline the mechanism that how more reagent will help in more degradation of the pollutants. Literature in discussion is also added that states that affect of catalysts and UV irradiation separately on degradation of PAHs.

Page no 9 line 281-287

5. 
   Can the authors provide critical views on using semiconducting metal-oxide nanoparticles
   (e.g., TiO2, Cu2O, ZnO) as photocatalysts under electromagnetic light irradiation for PAH
   degradation and include their views into the manuscript? These materials are popularly
   being investigated in the field of photocatalysis and would also make this manuscript
   impactful.

A whole new paragraph is added in the discussion section which outline the use of semiconductors as photocatalysts under electromagnetic irradiation for PAH degradation and comparison with current study is made.

Page no 9 line 263-271

6 The experiments reported in this manuscript utilizes a specific light source with UV
wavelength (306 nm), is it accurately 306 nm alone (like laser) or does the UV light source
has a broader range (wavelength vs intensity) of the source. Could the authors comment on
the applicability of alternative light sources like visible light or solar irradiation for
activating catalysts or directly degrading PAHs? This insight could be useful in identifying
more energy-efficient for large-scale applications.

The sunlight is composed of three components namely visible light (400-700 nm), UVA light (320-400 nm) and UVB light (280-320 nm) and among them visible light and UVA have best results on degradation of PAHs. Similar has been added in the intro section.

In this experiment, UV radiation of 306 nm was applied because it was best suited to our experimental conditions, moreover previous literature have proved that optimum UV wavelength ranges between 250-350 for Photocatalysis.

Moreover the use of light energy depends on the type of catalyst use. For example TiO2 perform only in ultraviolet rays in the solar spectrum owing to wide band gap energy and using certain materials like doping agents can help in extension of optical absorbing response from UV to visible wavelengths. In this regard few lines explaining the use of different light sources is added in the introduction section

Page 2, line no 49-56

7. 
   This research contribution acknowledges the importance of catalyst reusability but doesn't
   discuss regeneration strategies for the iron-based catalyst or explored potential alternatives.
   Can the authors comment on or elaborate on specific methods attempted for catalyst
   regeneration and their effectiveness in restoring activity?

No, we did not worked on the regeneration of the catalyst.

8. 
   To comprehensively evaluate this potential risk, did the authors conduct leaching tests to
   quantify the extent of metal release over extended treatment periods? Specifying the
   leaching medium used (e.g., a simulated soil solution with defined pH and ionic strength)
   and the analytical techniques employed for metal identification and quantification of these
   leachates? The reviewer also suggests to give the authors critical insights and comment on
   it, possibly including it in the manuscript.

Response: No, we did not conduct the leaching tests, however its suggestion is now added in the conclusion section. page no. 11  line 394-396

Page no.
9. The reviewer suggests the authors to perform intensity and wavelength depend studies in
the future contributions, for gaining more insights into the reaction mechanisms and
developing catalysts with high activity, selectivity and stability.

Response: Few lines about future prospects of the study are added in conclusion section. Page no 11, line no 396-398.

10. 
    The introduction effectively highlights Polycyclic aromatic hydrocarbons (PAHs) and its
    adverse health effects. While Fenton-like reactions and conventional solvent extraction are
    discussed, the introduction does not adequately discuss or mention other established
    photocatalytic methods used in pollution mitigation applications from a catalysts
    perspective. The introduction limits the understanding of the broader audience of catalysts
    and does not discuss the advantages of other metals (e.g., Pt, Au, Ag) and metal-oxides
    materials like TiO2, Cu2O, FeP, CeO2 used in photocatalytic reactions, and discuss their
    unique properties and photocatalytic performances, how the heating effect was decoupled.
    Metal oxides play a crucial role in many novel photocatalytic processes, including
    degradation of pollutants. The introduction does not discuss the novel phenomena such as
    plasmonic, mie resonances induced electron transfer, effect of clustering, recombination
    mechanisms, charge-carrier dynamics, pathways, effect of shape and size of these

nanostructures, and other sensitization mechanisms. The manuscript could benefit and can
be made more impactful from thorough and concise discussion on the various alternative
photocatalytic technologies used for photocatalytic remediation. Adding a concise
discussion on the above mentioned drawbacks ensures that readers have a holistic
understanding of the different materials and technologies being explored in this field.
Below are some articles for the authors to cite that directly focus on describing these
methods and their applications:
o Highly Efficient Photocatalytic Degradation of Tetracycline by Modifying UiO-66 via
Different Regulation Strategies
o Photocarrier Recombination Dynamics in Highly Scattering Cu2O Nanocatalyst Clusters
o Photocatalytic degradation of polycyclic aromatic hydrocarbon benzo[a]pyrene by iron
oxides and identification of degradation products
o Structure–Property–Performance Relationships of Cuprous Oxide Nanostructures for
Dielectric Mie Resonance-Enhanced Photocatalysis
o Formation of Iron Phosphide Nanobundles from an Iron Oxyhydroxide Precursor
o Pyrene contaminated soil remediation using microwave/magnetite activated persulfate
oxidation
o Tuning Catalytic Activity and Selectivity in Photocatalysis on Mie-Resonant Cuprous
Oxide Particles: Distinguishing Electromagnetic Field Enhancement Effect from the
Heating Effect
o Review of Techniques for the Removal of Polycyclic Aromatic Hydrocarbons from
Produced Water
o Carrier dynamics in cuprous oxide-based nanoparticles and heterojunctions
o Removal of Polycyclic Aromatic Hydrocarbons (PAHs) from Industrial Soil with Solar
and UV Light

All the possible and relevant literature has been added in the introduction as well as discussion section.

New comments:

 

R1

 

Comments and Suggestions for Authors

The reviewer suggests the authors to consider providing the responses to the review comments in a more detailed and technical perspective. The reviewer requests the authors to improve the introduction section as it still does not adequately discuss or mention other established photocatalytic methods used in pollution mitigation applications from a catalysts perspective.

 

Heterogeneous  semiconductor  photocatalysis  [2,  3]  has  been

extensively  studied  and  it  is  a  promising  approach  for  degradation  of  a  large  number  of  organic

pollutants as it  is also found to  be cost effective.  Photocatalysis finds a  good  scope in the  field  of

creating renewable energy resources and also for cleaning environment.

  Semiconductor  based  photocatalysis  has  been  extensively  studied  for  its  environmental

applications and demonstrated to be a cleanup process [4-8].

 

Heterogeneous photocatalysis is a part

of  Advanced  Oxidation  Processes  (AOPs)  and  it  is  a  process  of  great  potential  for  pollutant

degradation and waste water treatment [9-11].

Response: The manuscript is revised and literature related to other photocatalytic methods Data added page no 2 line no 52 to 66

 

For reviewer the questions the reviewer requests the authors to provide the authors critical perspective as well and possible adding their views and critical responses it into the manuscript

 

For example

 

For the reviewer comment 1. The choice of wavelength of light depends on the resonances occurring on the catalysts used for the specific reaction. It is not necessary that UV light will be the best choice for all photocatalytic processes.

 

 Response: In addition to the previous improvement, the use of light sources are discussed in the introduction section on Page 2, line no 49-56

 

 

The response the reviewer comment 4 is not clear. The reviewer question is on the research indicates a synergistic effect between FeCl3/H2O2 and UV light. Could the authors quantify this by comparing the degradation rates of the combined treatment with those of the individual treatments (FeCl3/H2O2 alone and UV light alone)?”

 

 

Response: Few lines related to the above mentioned individual as well as combined effects of the treatments on degradation of PAHs is mentioned on Page no 9 line 281-287

 

For the reviewer comment 6, the authors have responded “The sunlight is composed of three components namely visible light (400-700 nm), UVA light (320-400 nm) and UVB light (280-320 nm) … In this experiment, UV radiation of 306 nm was applied because it was best suited to our experimental conditions, moreover previous literature have proved that optimum UV wavelength ranges between 250-350 for Photocatalysis.” The solar spectrum incident on earth is shown in the below figure suggesting the entire electromagnetic radiation ranging from 250-2500 nm wavelengths and their respective intensities. The optimum wavelength for this reaction depends on the shape and size of the catalysts, the absorption of the PAH molecules (to consider direct sensitization effect due to interactions of UV light and the molecules), intensity of the UV light used for experiments. The literature suggestions might not be the final and optimum wavelength.

 

 The reviewer strongly recommends the authors to consider giving critical technical responses and also improve the manuscript with the insights of technical research.

 

The reviewer strongly recommends that the authors consider adding all the responses to comments provided by the reviewers into the manuscript. Doing so will significantly enhance the quality and impact of this research work. Integrating these suggestions will enhance the study's comprehensiveness and impact, benefiting the scientific community, authors, and potential readers of the manuscript.

 

For the reviewer comment 7 The reviewer does understands the practical limitations of performing research and scope of this work, but the authors can provide their critical views and their elaborate thoughts on specific methods for catalyst regeneration and their effectiveness in restoring activity and consider writing them into the manuscript in the discussion section adding value to this impactful work?

 

For the reviewer comment 10

 

The introduction does not discuss the novel phenomena such as plasmonic, mie resonances induced electron transfer, effect of clustering, recombination mechanisms, charge-carrier dynamics, pathways, effect of shape and size of these nanostructures, and other sensitization mechanisms which directly relate and improve this manuscript. The manuscript could benefit and can be made more impactful from a thorough and concise discussion on the various alternative photocatalytic technologies used for photocatalytic remediation. Adding a concise discussion on the above mentioned drawbacks ensures that readers have a holistic understanding of the different materials and technologies being explored in this field.

 

Response: alternative photocatalytic technologies relevant literature has been added on page 2 line no 72-85.

 

The authors did not improve the introduction section in these aspects. The reviewer suggests the authors to provide a concise discussion and few lines on them which can improve the manuscript. Detailing more only about photo-fenton reaction is not adding value to the introduction section. This part maybe moved to the discussion section as the authors may consider.

The reviewer suggests the authors to reconsider adding responses to the version 1 of reviewer comments below and consider citing the literature suggested which directly relate to the above discussed mechanisms and photocatalytic processes.

Response: We have tried to incorporate all the suggestions by keeping in view the above-mentioned studies. The addition is made in red text while page and line no are also mentioned in the response file.

Author Response

Subject: Submission of Revised Manuscript (2nd Revision)

Dear Editor,

On behalf of my co-authors, I am pleased to submit the second revised version of our manuscript entitled:

“Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) Using UV/FeCl₃ in Industrial Soil.”

We have carefully addressed and incorporated all the comments and suggestions provided by the reviewers. The newly added data, analyses, and clarifications are highlighted in blue-colored text within the revised manuscript for easy identification.

We believe that the revisions have substantially improved the quality and clarity of the manuscript, and we sincerely thank you and the reviewers for the constructive feedback and valuable guidance.

We respectfully resubmit the revised manuscript for your kind consideration and hope that it will now meet the journal’s standards for publication.

Sincerely,

Author Response File: Author Response.pdf

Reviewer 2 Report (Previous Reviewer 3)

Comments and Suggestions for Authors

It can be accepted. 

Author Response

Thanks for the recommendation for the acceptance of the paper

Author Response File: Author Response.pdf

Reviewer 3 Report (New Reviewer)

Comments and Suggestions for Authors

The authors have carefully addressed all the requested revisions. I recommend acceptance of the manuscript in its current form.

Author Response

The conclusion section has been revised as per the suggestions.

Thanks for the recommendation for the acceptance of the paper.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report (Previous Reviewer 1)

Comments and Suggestions for Authors

None

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The reviewer strongly recommends that the authors consider adding all the responses to comments provided by the reviewers into the manuscript. Doing so will significantly enhance the quality and impact of this research work. Integrating these suggestions will enhance the study's comprehensiveness and impact, benefiting the scientific community, authors, and potential readers of the manuscript.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

English language editing and spelling errors need to be verified and formatted correctly. For example in the Conclusion section line number 295 the word "oxadiazon-catalysis" is having an error. 

Author Response

Reviewer 1

The paper entitled “Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic
Hydrocarbons (PAHs) Using UV/FeCl3 in Industrial Soil” is a novel work. This study investigates using Fenton reagent (FeCl₃/H₂O₂) for degrading polycyclic aromatic hydrocarbons (PAHs) in contaminated soil. Higher concentrations of FeCl₃ and H₂O₂ resulted in faster degradation of PAHs, likely due to increased hydroxyl radical generation. This approach has the potential to remediate PAH-contaminated soil quickly and effectively. The present manuscript in its present form has minor corrections that includes captions errors and a few scientific shortcomings that needs to be addressed carefully. The manuscript in the present form also has some grammatical errors and also scientific shortcomings that needs to be addressed significantly and revise the manuscript. For instance:

1. 
   This research work utilizes a specific UV wavelength (306 nm). Can the authors comment
   on the choice of this wavelength? Are there alternative UV wavelengths that might be more
   efficient for PAH degradation, considering factors like penetration depth in soil?

Response: There have been many studies which tested the affect of different UV wavelengths on the degradation of PAHs i.e. 250-700 nm, however we choose this wavelength because maximum studies gave best results at wavelengths of 250-350 nm and this specific UV wavelength was best suited under our experimental set up.

2. The authors investigated decontamination in industrial soil. How does the effectiveness of
   the treatment change depending on the soil composition (e.g., clay content, organic matter
   content)?

Response: Studies relevant to the affect of UV radiation on PAHs decomposition and how soil properties affect its performance are now incorporated in the introduction section. 

3. 
   This impact research explores the impact of FeCl₃/H₂O₂ and UV light on PAH
   degradation, did the authors perform any control experiments performed without the
   catalyst or UV irradiation to isolate their individual contributions and can the authors
   comment on the degradation mechanisms and electron transfer scheme for the degradation
   of pollutants with schematic diagram, as this work would garner more interest in the
   broader readership of this journal?

Response:Yes this work has explored the impact of UV radiation without catalysts or oxidizing agent. That treatment was given the name of control and is presented in table 1. Whereas the treatments with various concentrations of FeCl₃ and H₂O₂ are presented in table no 2 and 3.

4. 
   This research contribution suggests a synergistic effect between FeCl₃/H₂O₂ and UV light.
   Can the authors quantify this synergy by comparing the degradation rates achieved with
   the combined treatment compared to individual treatments (Fenton reagent alone or UV
   light alone)?

Response:Yes the results of each treatment is discussed in details, moreover studies are added in discussion section which outline the mechanism that how more reagent will help in more degradation of the pollutants.

5. 
   Can the authors provide critical views on using semiconducting metal-oxide nanoparticles
   (e.g., TiO₂, Cu₂O, ZnO) as photocatalysts under electromagnetic light irradiation for PAH
   degradation and include their views into the manuscript? These materials are popularly
   being investigated in the field of photocatalysis and would also make this manuscript
   impactful.

Response:A whole new paragraph is added in the discussion section which outline the use of semiconductors as photocatalysts under electromagnetic irradiation for PAH degradation and comparison with current study is made.

6The experiments reported in this manuscript utilizes a specific light source with UV
wavelength (306 nm), is it accurately 306 nm alone (like laser) or does the UV light source
has a broader range (wavelength vs intensity) of the source. Could the authors comment on
the applicability of alternative light sources like visible light or solar irradiation for
activating catalysts or directly degrading PAHs? This insight could be useful in identifying
more energy-efficient for large-scale applications.

Response:The sunlight is composed of three components namely visible light (400-700 nm), UVA light (320-400 nm) and UVB light (280-320 nm) and among them visible light and UVA have best results on degradation of PAHs. Similar has been added in the intro section.

In this experiment, UV radiation of 306 nm was applied because it was best suited to our experimental conditions, moreover previous literature have proved that optimum UV wavelength ranges between 250-350 for Photocatalysis.
7. This research contribution acknowledges the importance of catalyst reusability but doesn't
discuss regeneration strategies for the iron-based catalyst or explored potential alternatives.
Can the authors comment on or elaborate on specific methods attempted for catalyst
regeneration and their effectiveness in restoring activity?

Response:No, we did not worked on the regeneration of the catalyst.

8. To comprehensively evaluate this potential risk, did the authors conduct leaching tests to
   quantify the extent of metal release over extended treatment periods? Specifying the
   leaching medium used (e.g., a simulated soil solution with defined pH and ionic strength)
   and the analytical techniques employed for metal identification and quantification of these
   leachates? The reviewer also suggests to give the authors critical insights and comment on
   it, possibly including it in the manuscript.

Response: There is a good suggestion to add leaching test which we definitely add in our coming experiment.

9. The reviewer suggests the authors to perform intensity and wavelength depend studies in
   the future contributions, for gaining more insights into the reaction mechanisms and
   developing catalysts with high activity, selectivity and stability.

Response: Noted.

10. The introduction effectively highlights Polycyclic aromatic hydrocarbons (PAHs) and its
    adverse health effects. While Fenton-like reactions and conventional solvent extraction are
    discussed, the introduction does not adequately discuss or mention other established
    photocatalytic methods used in pollution mitigation applications from a catalysts
    perspective. The introduction limits the understanding of the broader audience of catalysts
    and does not discuss the advantages of other metals (e.g., Pt, Au, Ag) and metal-oxides
    materials like TiO₂, Cu₂O, FeP, CeO₂ used in photocatalytic reactions, and discuss their
    unique properties and photocatalytic performances, how the heating effect was decoupled.
    Metal oxides play a crucial role in many novel photocatalytic processes, including
    degradation of pollutants. The introduction does not discuss the novel phenomena such as
    plasmonic, mie resonances induced electron transfer, effect of clustering, recombination
    mechanisms, charge-carrier dynamics, pathways, effect of shape and size of these nanostructures, and other sensitization mechanisms. The manuscript could benefit and can
    be made more impactful from thorough and concise discussion on the various alternative
    photocatalytic technologies used for photocatalytic remediation. Adding a concise
    discussion on the above mentioned drawbacks ensures that readers have a holistic
    understanding of the different materials and technologies being explored in this field.
    Below are some articles for the authors to cite that directly focus on describing these
    methods and their applications:
    o Highly Efficient Photocatalytic Degradation of Tetracycline by Modifying UiO-66 via
    Different Regulation Strategies
    o Photocarrier Recombination Dynamics in Highly Scattering Cu2O Nanocatalyst Clusters
    o Photocatalytic degradation of polycyclic aromatic hydrocarbon benzo[a]pyrene by iron
    oxides and identification of degradation products
    o Structure–Property–Performance Relationships of Cuprous Oxide Nanostructures for
    Dielectric Mie Resonance-Enhanced Photocatalysis
    o Formation of Iron Phosphide Nanobundles from an Iron Oxyhydroxide Precursor
    o Pyrene contaminated soil remediation using microwave/magnetite activated persulfate
    oxidation
    o Tuning Catalytic Activity and Selectivity in Photocatalysis on Mie-Resonant Cuprous
    Oxide Particles: Distinguishing Electromagnetic Field Enhancement Effect from the
    Heating Effect
    o Review of Techniques for the Removal of Polycyclic Aromatic Hydrocarbons from
    Produced Water
    o Carrier dynamics in cuprous oxide-based nanoparticles and heterojunctions
    o Removal of Polycyclic Aromatic Hydrocarbons (PAHs) from Industrial Soil with Solar
    and UV Light

Response: All the possible and relevant literature has been added in the introduction as well as discussion section.

Reviewer 2 Report

Comments and Suggestions for Authors

Saeid et al reported that the “Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) Using UV/FeCL₃ in Industrial Soil”. The study looks interesting to see the degradation of PAHs with 306 nm UV light, and different concentrations of FeCl₃ and H₂O₂. However, most of the studies in this manuscript does not provide evidence. The in-depth mechanism studies are not there in the manuscript. Authors should mention the novelty of this work compared with the prior literature. Also, during the mechanism explained in the discussion section what is the evidence for the formation of FeO, free radicals of OH. In this study authors used 306 nm UV light is there any specific reason for it and what is the power of this 306 nm source. Authors should mention the units in the figures. Therefore, I do not think this manuscript has worth to publishing in the present form in Catalysts journal. Please also find some minor errors in the paper here.

1.      Please use the abbreviation for Polycyclic aromatic hydrocarbons in page 1, line 38 page 2, line 65, and page 9, lines 239, 249.

2.      Please comment on how the degradation rate of PAHs is correlated with H2O2-Fe2+ ratio and H2O2 concentrations.

3.      Please have space between 306 and nm.

4.      Care should be taken in writing chemical formulas in the conclusions, for instance: H2O2, FeCL3 the suffixes were missing.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Enough care should be given in formatting the manuscript.

Author Response

REVIEWER 2

Saeid et al reported that the “Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) Using UV/FeCL3 in Industrial Soil”. The study looks interesting to see the degradation of PAHs with 306 nm UV light, and different concentrations of FeCl₃ and H₂O₂. However, most of the studies in this manuscript does not provide evidence. The in-depth mechanism studies are not there in the manuscript. Authors should mention the novelty of this
work compared with the prior literature. Also, during the mechanism explained in the discussion section what is the evidence for the formation of FeO, free radicals of OH. In this study authors used 306 nm UV light is there any specific reason for it and what is the power of this 306 nm source. Authors should mention the units in the figures. Therefore, I do not think this manuscript has worth to publishing in the present form in Catalysts journal. Please also find some minor errors in the paper here.

Response: Thanks for suggestions

1. Please use the abbreviation for Polycyclic aromatic hydrocarbons in page 1, line 38 page
   2, line 65, and page 9, lines 239, 249.

Response:Done as suggested .

2. Please comment on how the degradation rate of PAHs is correlated with H₂O₂-Fe²⁺ ratio
   and H₂O₂ concentrations.

Response:Added in discussion section.

3. Please have space between 306 and nm.

Response:The space is inserted between 306 and nm in the whole manuscript.

4. Care should be taken in writing chemical formulas in the conclusions, for instance:
   H2O2, FeCL3 the suffixes were missing.

Response:The abbreviated as well as full forms of the said compounds is now mentioned in the conclusion section.

 

Reviewer 3 Report

Comments and Suggestions for Authors

1.      Line 63-68: “Using photocatalytic decomposition of polycyclic aromatic hydrocarbons under UV light in the presence of some semiconductor materials (FeCL3)”. FeCl3 is not a semiconductor material.

2.      Four chemical reactions have been written for the production of OH radical. None of the reactions involve irradiation. However, in the text a term UV light has been used for it.

3.      Line 73, “The cathode is the target of H2O2, in contrast…………’” It is meaningless and an awkward statement.

4.      Line 75, “Mechanism Fenton process doing decomposition of organic compounds via oxidation …………” Meaning less and awkward sentence.

5.      Similarly, the English of Introduction section upto the end is awkward. The English is not acceptable.

6.      Line 114-135; All the sentences are meaningless and awkward.

7.      Figure 3 and Figure 4; what are the units on x-axis and y-axis?

 

8.      Overall, the English is very poor. This paper is not suitable for publication in Catalysts.

Comments on the Quality of English Language

English is not acceptable.

Author Response

Reviewer 3

 

Top of Form

Yes	Can be improved	Must be improved	Not applicable
Does the introduction provide sufficient background and include all relevant references?	( )	( )	(x)	( )
Is the research design appropriate?	( )	( )	(x)	( )
Are the methods adequately described?	( )	(x)	( )	( )
Are the results clearly presented?	( )	( )	(x)	( )
Are the conclusions supported by the results?	( )	( )	(x)	( )

Comments and Suggestions for Authors

1. Line 63-68: “Using photocatalytic decomposition of polycyclic aromatic hydrocarbons under UV light in the presence of some semiconductor materials (FeCL3)”. FeCl3 is not a semiconductor material.

Response:The word ‘semiconductor’ is replaced by ‘iron catalyst’ in the said line.

2. Four chemical reactions have been written for the production of OH radical. None of the reactions involve irradiation. However, in the text a term UV light has been used for it.

Response:The new and corrected chemical equations are added

3. Line 73, “The cathode is the target of H2O2, in contrast…………’” It is meaningless and an awkward statement.

Response:This line/statement has been deleted.

4. Line 75, “Mechanism Fenton process doing decomposition of organic compounds via oxidation …………” Meaning less and awkward sentence.

Response:The sentence has been deleted and replaced by the actual study mentioned via citation.

5. Similarly, the English of Introduction section upto the end is awkward. The English is not acceptable.

Response:The overall English language of the manuscript has been revised

6. Line 114-135; All the sentences are meaningless and awkward.

Response:English language has been revised and sentence structures are rechecked.

7. Figure 3 and Figure 4; what are the units on x-axis and y-axis?

 Response:The units are now added on the x and y axis in figures.

8. Overall, the English is very poor. This paper is not suitable for publication in Catalysts.

Response:The whole manuscript is revised with special focus on English language and sentence errors.

Reviewer 4 Report

Comments and Suggestions for Authors 1.     Please provide a more quantitative abstract.

2.     Please add a brief illustration of the e/h production and reactive radical species in heterogeneous photocatalysis, by reading Molecules 2023, 28, 6848 and J. Mol. Struct., 2024, 1312,138501.

3.     Pls add the DRS data, it is important.

4.     The effects of the scavenging agents should be done.

5.     Please deeply revise the English language level.

6.     Please improve the resolution of Fig. 1.

7.     The author should carefully review the manuscript for formatting and punctuation throughout. Such as FeCL3 should be FeCl3

8.     The catalyltic part should be illustrated in detail.

Comments on the Quality of English Language

revised in detail

Author Response

Reviewer  4

(x) I would not like to sign my review report
( ) I would like to sign my review report

Quality of English Language

( ) I am not qualified to assess the quality of English in this paper
( ) English very difficult to understand/incomprehensible
( ) Extensive editing of English language required
(x) Moderate editing of English language required
( ) Minor editing of English language required
( ) English language fine. No issues detected

 

	Yes	Can be improved	Must be improved	Not applicable
Does the introduction provide sufficient background and include all relevant references?	( )	(x)	( )	( )
Is the research design appropriate?	( )	(x)	( )	( )
Are the methods adequately described?	( )	(x)	( )	( )
Are the results clearly presented?	( )	(x)	( )	( )
Are the conclusions supported by the results?	( )	(x)	( )	( )

Comments and Suggestions for Authors

1. Please provide a more quantitative abstract.
2. Please add a brief illustration of the e/h production and reactive radical species in heterogeneous photocatalysis, by reading Molecules 2023, 28, 6848 and J. Mol. Struct., 2024, 1312,138501.

Response:It has been added in discussion section

3. Pls add the DRS data, it is important.
4. The effects of the scavenging agents should be done.
5. Please deeply revise the English language level.

Response: The English language and sentence structure is improved in the whole manuscript.

6. Please improve the resolution of Fig. 1.

Response: The resolution of fog has been improved.

7. The author should carefully review the manuscript for formatting and punctuation throughout. Such as FeCL₃ should be FeCl₃

Response: The whole manuscript is rechecked and the FeCL₃ is changed into FeCl₃.

8. The catalyltic part should be illustrated in detail.

Response: Done as suggested. New data has been added

Comments on the Quality of English Language

Response: revised in detail

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The reviewer suggests the authors to consider providing the responses to the review comments in a more detailed and technical perspective. The reviewer requests the authors to improve the introduction section as it still does not adequately discuss or mention other established photocatalytic methods used in pollution mitigation applications from a catalysts perspective.

For reviewer the questions the reviewer requests the authors to provide the authors critical perspective as well and possible adding their views and critical responses it into the manuscript

For example

For the reviewer comment 1. The choice of wavelength of light depends on the resonances occurring on the catalysts used for the specific reaction. It is not necessary that UV light will be the best choice for all photocatalytic processes.

The response the reviewer comment 4 is not clear. The reviewer question is on the research indicates a synergistic effect between FeCl₃/H₂O₂ and UV light. Could the authors quantify this by comparing the degradation rates of the combined treatment with those of the individual treatments (FeCl₃/H₂O₂ alone and UV light alone)?”

For the reviewer comment 6, the authors have responded “The sunlight is composed of three components namely visible light (400-700 nm), UVA light (320-400 nm) and UVB light (280-320 nm) … In this experiment, UV radiation of 306 nm was applied because it was best suited to our experimental conditions, moreover previous literature have proved that optimum UV wavelength ranges between 250-350 for Photocatalysis.” The solar spectrum incident on earth is shown in the below figure suggesting the entire electromagnetic radiation ranging from 250-2500 nm wavelengths and their respective intensities. The optimum wavelength for this reaction depends on the shape and size of the catalysts, the absorption of the PAH molecules (to consider direct sensitization effect due to interactions of UV light and the molecules), intensity of the UV light used for experiments. The literature suggestions might not be the final and optimum wavelength.

 The reviewer strongly recommends the authors to consider giving critical technical responses and also improve the manuscript with the insights of technical research.

The reviewer strongly recommends that the authors consider adding all the responses to comments provided by the reviewers into the manuscript. Doing so will significantly enhance the quality and impact of this research work. Integrating these suggestions will enhance the study's comprehensiveness and impact, benefiting the scientific community, authors, and potential readers of the manuscript.

For the reviewer comment 7 The reviewer does understands the practical limitations of performing research and scope of this work, but the authors can provide their critical views and their elaborate thoughts on specific methods for catalyst regeneration and their effectiveness in restoring activity and consider writing them into the manuscript in the discussion section adding value to this impactful work?

For the reviewer comment 10

The introduction does not discuss the novel phenomena such as plasmonic, mie resonances induced electron transfer, effect of clustering, recombination mechanisms, charge-carrier dynamics, pathways, effect of shape and size of these nanostructures, and other sensitization mechanisms which directly relate and improve this manuscript. The manuscript could benefit and can be made more impactful from a thorough and concise discussion on the various alternative photocatalytic technologies used for photocatalytic remediation. Adding a concise discussion on the above mentioned drawbacks ensures that readers have a holistic understanding of the different materials and technologies being explored in this field. 

The authors did not improve the introduction section in these aspects. The reviewer suggests the authors to provide a concise discussion and few lines on them which can improve the manuscript. Detailing more only about photo-fenton reaction is not adding value to the introduction section. This part maybe moved to the discussion section as the authors may consider.

The reviewer suggests the authors to reconsider adding responses to the version 1 of reviewer comments below and consider citing the literature suggested which directly relate to the above discussed mechanisms and photocatalytic processes. 

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Moderate editing of English language required

Author Response

Reviewer 1

Previous comments

The paper entitled “Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic
Hydrocarbons (PAHs) Using UV/FeCl3 in Industrial Soil” is a novel work. This study investigates
using Fenton reagent (FeCl3/H2O2) for degrading polycyclic aromatic hydrocarbons (PAHs) in
contaminated soil. Higher concentrations of FeCl3 and H2O2 resulted in faster degradation of
PAHs, likely due to increased hydroxyl radical generation. This approach has the potential to
remediate PAH-contaminated soil quickly and effectively. The present manuscript in its present
form has minor corrections that includes captions errors and a few scientific shortcomings that
needs to be addressed carefully. The manuscript in the present form also has some grammatical
errors and also scientific shortcomings that needs to be addressed significantly and revise the
manuscript. For instance:
1. This research work utilizes a specific UV wavelength (306 nm). Can the authors comment
on the choice of this wavelength? Are there alternative UV wavelengths that might be more
efficient for PAH degradation, considering factors like penetration depth in soil?

There have been many studies which tested the affect of different UV wavelengths on the degradation of PAHs i.e. 250-700 nm, however we choose this wavelength because maximum studies gave best results at wavelengths of 250-350 nm and this specific UV wavelength was best suited under our experimental set up.

Moreover the use of light energy depends on the type of catalyst use. For example TiO2 perform only in ultraviolet rays in the solar spectrum owing to wide band gap energy and using certain materials like doping agents can help in extension of optical absorbing response from UV to visible wavelengths. In this regard few lines explaining the use of different light sources is added in the introduction section

Page 2, line no 49-56

2. 
   The authors investigated decontamination in industrial soil. How does the effectiveness of
   the treatment change depending on the soil composition (e.g., clay content, organic matter
   content)?

Studies relevant to the affect of UV radiation on PAHs decomposition and how soil properties affect its performance are now incorporated in the introduction section.  The text is colored as red page no 4, line no 167-175

3. 
   This impactful research explores the impact of FeCl3/H2O2 and UV light on PAH
   degradation, did the authors perform any control experiments performed without the
   catalyst or UV irradiation to isolate their individual contributions and can the authors
   comment on the degradation mechanisms and electron transfer scheme for the degradation
   of pollutants with schematic diagram, as this work would garner more interest in the
   broader readership of this journal?

Yes this work has explored the impact of UV radiation without catalysts or oxidizing agent. That treatment was given the name of control and is presented in table 1. Whereas the treatments with various concentrations of FeCl3 and H2O2 are presented in table no 2 (page 6 ) and 3 (page 7).

4. 
   This research contribution suggests a synergistic effect between FeCl3/H2O2 and UV light.
   Can the authors quantify this synergy by comparing the degradation rates achieved with
   the combined treatment compared to individual treatments (Fenton reagent alone or UV
   light alone)?

Yes the results of each treatment is discussed in details, moreover studies are added in discussion section which outline the mechanism that how more reagent will help in more degradation of the pollutants. Literature in discussion is also added that states that affect of catalysts and UV irradiation separately on degradation of PAHs.

Page no 9 line 281-287

5. 
   Can the authors provide critical views on using semiconducting metal-oxide nanoparticles
   (e.g., TiO2, Cu2O, ZnO) as photocatalysts under electromagnetic light irradiation for PAH
   degradation and include their views into the manuscript? These materials are popularly
   being investigated in the field of photocatalysis and would also make this manuscript
   impactful.

A whole new paragraph is added in the discussion section which outline the use of semiconductors as photocatalysts under electromagnetic irradiation for PAH degradation and comparison with current study is made.

Page no 9 line 263-271

6 The experiments reported in this manuscript utilizes a specific light source with UV
wavelength (306 nm), is it accurately 306 nm alone (like laser) or does the UV light source
has a broader range (wavelength vs intensity) of the source. Could the authors comment on
the applicability of alternative light sources like visible light or solar irradiation for
activating catalysts or directly degrading PAHs? This insight could be useful in identifying
more energy-efficient for large-scale applications.

The sunlight is composed of three components namely visible light (400-700 nm), UVA light (320-400 nm) and UVB light (280-320 nm) and among them visible light and UVA have best results on degradation of PAHs. Similar has been added in the intro section.

In this experiment, UV radiation of 306 nm was applied because it was best suited to our experimental conditions, moreover previous literature have proved that optimum UV wavelength ranges between 250-350 for Photocatalysis.

Moreover the use of light energy depends on the type of catalyst use. For example TiO2 perform only in ultraviolet rays in the solar spectrum owing to wide band gap energy and using certain materials like doping agents can help in extension of optical absorbing response from UV to visible wavelengths. In this regard few lines explaining the use of different light sources is added in the introduction section

Page 2, line no 49-56

7. 
   This research contribution acknowledges the importance of catalyst reusability but doesn't
   discuss regeneration strategies for the iron-based catalyst or explored potential alternatives.
   Can the authors comment on or elaborate on specific methods attempted for catalyst
   regeneration and their effectiveness in restoring activity?

No, we did not worked on the regeneration of the catalyst.

8. 
   To comprehensively evaluate this potential risk, did the authors conduct leaching tests to
   quantify the extent of metal release over extended treatment periods? Specifying the
   leaching medium used (e.g., a simulated soil solution with defined pH and ionic strength)
   and the analytical techniques employed for metal identification and quantification of these
   leachates? The reviewer also suggests to give the authors critical insights and comment on
   it, possibly including it in the manuscript.

Response: No, we did not conduct the leaching tests, however its suggestion is now added in the conclusion section. page no. 11  line 394-396

Page no.
9. The reviewer suggests the authors to perform intensity and wavelength depend studies in
the future contributions, for gaining more insights into the reaction mechanisms and
developing catalysts with high activity, selectivity and stability.

Response: Few lines about future prospects of the study are added in conclusion section. Page no 11, line no 396-398.

10. 
    The introduction effectively highlights Polycyclic aromatic hydrocarbons (PAHs) and its
    adverse health effects. While Fenton-like reactions and conventional solvent extraction are
    discussed, the introduction does not adequately discuss or mention other established
    photocatalytic methods used in pollution mitigation applications from a catalysts
    perspective. The introduction limits the understanding of the broader audience of catalysts
    and does not discuss the advantages of other metals (e.g., Pt, Au, Ag) and metal-oxides
    materials like TiO2, Cu2O, FeP, CeO2 used in photocatalytic reactions, and discuss their
    unique properties and photocatalytic performances, how the heating effect was decoupled.
    Metal oxides play a crucial role in many novel photocatalytic processes, including
    degradation of pollutants. The introduction does not discuss the novel phenomena such as
    plasmonic, mie resonances induced electron transfer, effect of clustering, recombination
    mechanisms, charge-carrier dynamics, pathways, effect of shape and size of these

nanostructures, and other sensitization mechanisms. The manuscript could benefit and can
be made more impactful from thorough and concise discussion on the various alternative
photocatalytic technologies used for photocatalytic remediation. Adding a concise
discussion on the above mentioned drawbacks ensures that readers have a holistic
understanding of the different materials and technologies being explored in this field.
Below are some articles for the authors to cite that directly focus on describing these
methods and their applications:
o Highly Efficient Photocatalytic Degradation of Tetracycline by Modifying UiO-66 via
Different Regulation Strategies
o Photocarrier Recombination Dynamics in Highly Scattering Cu2O Nanocatalyst Clusters
o Photocatalytic degradation of polycyclic aromatic hydrocarbon benzo[a]pyrene by iron
oxides and identification of degradation products
o Structure–Property–Performance Relationships of Cuprous Oxide Nanostructures for
Dielectric Mie Resonance-Enhanced Photocatalysis
o Formation of Iron Phosphide Nanobundles from an Iron Oxyhydroxide Precursor
o Pyrene contaminated soil remediation using microwave/magnetite activated persulfate
oxidation
o Tuning Catalytic Activity and Selectivity in Photocatalysis on Mie-Resonant Cuprous
Oxide Particles: Distinguishing Electromagnetic Field Enhancement Effect from the
Heating Effect
o Review of Techniques for the Removal of Polycyclic Aromatic Hydrocarbons from
Produced Water
o Carrier dynamics in cuprous oxide-based nanoparticles and heterojunctions
o Removal of Polycyclic Aromatic Hydrocarbons (PAHs) from Industrial Soil with Solar
and UV Light

All the possible and relevant literature has been added in the introduction as well as discussion section.

New comments:

 

R1

 

Comments and Suggestions for Authors

The reviewer suggests the authors to consider providing the responses to the review comments in a more detailed and technical perspective. The reviewer requests the authors to improve the introduction section as it still does not adequately discuss or mention other established photocatalytic methods used in pollution mitigation applications from a catalysts perspective.

 

Heterogeneous  semiconductor  photocatalysis  [2,  3]  has  been

extensively  studied  and  it  is  a  promising  approach  for  degradation  of  a  large  number  of  organic

pollutants as it  is also found to  be cost effective.  Photocatalysis finds a  good  scope in the  field  of

creating renewable energy resources and also for cleaning environment.

  Semiconductor  based  photocatalysis  has  been  extensively  studied  for  its  environmental

applications and demonstrated to be a cleanup process [4-8].

 

Heterogeneous photocatalysis is a part

of  Advanced  Oxidation  Processes  (AOPs)  and  it  is  a  process  of  great  potential  for  pollutant

degradation and waste water treatment [9-11].

Response: The manuscript is revised and literature related to other photocatalytic methods Data added page no 2 line no 52 to 66

 

For reviewer the questions the reviewer requests the authors to provide the authors critical perspective as well and possible adding their views and critical responses it into the manuscript

 

For example

 

For the reviewer comment 1. The choice of wavelength of light depends on the resonances occurring on the catalysts used for the specific reaction. It is not necessary that UV light will be the best choice for all photocatalytic processes.

 

 Response: In addition to the previous improvement, the use of light sources are discussed in the introduction section on Page 2, line no 49-56

 

 

The response the reviewer comment 4 is not clear. The reviewer question is on the research indicates a synergistic effect between FeCl3/H2O2 and UV light. Could the authors quantify this by comparing the degradation rates of the combined treatment with those of the individual treatments (FeCl3/H2O2 alone and UV light alone)?”

 

 

Response: Few lines related to the above mentioned individual as well as combined effects of the treatments on degradation of PAHs is mentioned on Page no 9 line 281-287

 

For the reviewer comment 6, the authors have responded “The sunlight is composed of three components namely visible light (400-700 nm), UVA light (320-400 nm) and UVB light (280-320 nm) … In this experiment, UV radiation of 306 nm was applied because it was best suited to our experimental conditions, moreover previous literature have proved that optimum UV wavelength ranges between 250-350 for Photocatalysis.” The solar spectrum incident on earth is shown in the below figure suggesting the entire electromagnetic radiation ranging from 250-2500 nm wavelengths and their respective intensities. The optimum wavelength for this reaction depends on the shape and size of the catalysts, the absorption of the PAH molecules (to consider direct sensitization effect due to interactions of UV light and the molecules), intensity of the UV light used for experiments. The literature suggestions might not be the final and optimum wavelength.

 

 The reviewer strongly recommends the authors to consider giving critical technical responses and also improve the manuscript with the insights of technical research.

 

The reviewer strongly recommends that the authors consider adding all the responses to comments provided by the reviewers into the manuscript. Doing so will significantly enhance the quality and impact of this research work. Integrating these suggestions will enhance the study's comprehensiveness and impact, benefiting the scientific community, authors, and potential readers of the manuscript.

 

For the reviewer comment 7 The reviewer does understands the practical limitations of performing research and scope of this work, but the authors can provide their critical views and their elaborate thoughts on specific methods for catalyst regeneration and their effectiveness in restoring activity and consider writing them into the manuscript in the discussion section adding value to this impactful work?

 

For the reviewer comment 10

 

The introduction does not discuss the novel phenomena such as plasmonic, mie resonances induced electron transfer, effect of clustering, recombination mechanisms, charge-carrier dynamics, pathways, effect of shape and size of these nanostructures, and other sensitization mechanisms which directly relate and improve this manuscript. The manuscript could benefit and can be made more impactful from a thorough and concise discussion on the various alternative photocatalytic technologies used for photocatalytic remediation. Adding a concise discussion on the above mentioned drawbacks ensures that readers have a holistic understanding of the different materials and technologies being explored in this field.

 

Response: alternative photocatalytic technologies relevant literature has been added on page 2 line no 72-85.

 

The authors did not improve the introduction section in these aspects. The reviewer suggests the authors to provide a concise discussion and few lines on them which can improve the manuscript. Detailing more only about photo-fenton reaction is not adding value to the introduction section. This part maybe moved to the discussion section as the authors may consider.

The reviewer suggests the authors to reconsider adding responses to the version 1 of reviewer comments below and consider citing the literature suggested which directly relate to the above discussed mechanisms and photocatalytic processes.

Response: We have tried to incorporate all the suggestions by keeping in view the above-mentioned studies. The addition is made in red text while page and line no are also mentioned in the response file.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

It is hard to follow whether the authors have responded to the comments. The main comment was given here. I suggest authors to mention the response what has been done in the manuscript should also mention in the response letter. Also, in the present form of manuscript also contains some English mistakes and representation of chemical formulas.

Saeid et al reported that the “Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) Using UV/FeCL3 in Industrial Soil”. The study looks interesting to see the degradation of PAHs with 306 nm UV light, and different concentrations of FeCl3 and H2O2. However, most of the studies in this manuscript does not provide evidence. The in-depth mechanism studies are not there in the manuscript. Authors should mention the novelty of this work compared with the prior literature. Also, during the mechanism explained in the discussion section what is the evidence for the formation of FeO, free radicals of OH. In this study authors used 306 nm UV light is there any specific reason for it and what is the power of this 306 nm source. Authors should mention the units in the figures. Therefore, I do not think this manuscript has worth to publishing in the present form in Catalysts journal. Please also find some minor errors in the paper here.

Comments on the Quality of English Language

Few mistakes are still exist in the manuscript. Please take care of it.

Author Response

R2

Previous comments:

 

REVIEWER 2

Saeid et al reported that the “Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic
Hydrocarbons (PAHs) Using UV/FeCL3 in Industrial Soil”. The study looks interesting to see the
degradation of PAHs with 306 nm UV light, and different concentrations of FeCl3 and H2O2.
However, most of the studies in this manuscript does not provide evidence. The in-depth
mechanism studies are not there in the manuscript. Authors should mention the novelty of this
work compared with the prior literature. Also, during the mechanism explained in the discussion section what is the evidence for the formation of FeO, free radicals of OH. In this study authors
used 306 nm UV light is there any specific reason for it and what is the power of this 306 nm
source. Authors should mention the units in the figures. Therefore, I do not think this manuscript
has worth to publishing in the present form in Catalysts journal.

The discussion section is improved and comparison with previous studies is also made. For example page no 9, line 255-279 now has new studies which highlight the degradation process influenced by quantity of the catalyst, the type of pollutant affect the remediation procedure, the reduction and oxidation process is explained with reference to previous studies.

The units are now added in the figures (Fig 3,4,5) on page no. 6,7 and 8 respectively.

 

 

Please also find some minor
errors in the paper here.
1. Please use the abbreviation for Polycyclic aromatic hydrocarbons in page 1, line 38 page

2, line 65, and page 9, lines 239, 249.

Response: As we have revised the whole manuscript according to all reviewers comments, the mentioned change now appears on  other pages but we affirm that abbreviation for polycyclic aromatic hydrocarbons  is incorporated.
2. Please comment on how the degradation rate of PAHs is correlated with H2O2-Fe2+ ratio
and H2O2 concentrations.

In the discussion section new literature is added that outline the affect of catalysts and H2O2 and supported by previous literature as well page 9, line no 277-286
3. Please have space between 306 and nm.

The space is inserted between 306 and nm in the whole manuscript.
4. Care should be taken in writing chemical formulas in the conclusions, for instance:
H2O2, FeCL3 the suffixes were missing.

The abbreviated as well as full forms of the said compounds is now mentioned in the conclusion section.

 

New comments:

Comments and Suggestions for Authors

It is hard to follow whether the authors have responded to the comments. The main comment was given here. I suggest authors to mention the response what has been done in the manuscript should also mention in the response letter. Also, in the present form of manuscript also contains some English mistakes and representation of chemical formulas.

 

Saeid et al reported that the “Photocatalytic Remediation of Carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs) Using UV/FeCL3 in Industrial Soil”. The study looks interesting to see the degradation of PAHs with 306 nm UV light, and different concentrations of FeCl3 and H2O2. However, most of the studies in this manuscript does not provide evidence. The in-depth mechanism studies are not there in the manuscript. Authors should mention the novelty of this work compared with the prior literature. Also, during the mechanism explained in the discussion section what is the evidence for the formation of FeO, free radicals of OH. In this study authors used 306 nm UV light is there any specific reason for it and what is the power of this 306 nm source. Authors should mention the units in the figures. Therefore, I do not think this manuscript has worth to publishing in the present form in Catalysts journal. Please also find some minor errors in the paper here.

 

Comments on the Quality of English Language

Few mistakes are still exist in the manuscript. Please take care of it.

Response: The previous suggestions are incorporated accordingly and English language is also revised as per comments.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

1. The photocatalytic treatment method is not clear. Did the authors agitate/mix the soil sample and catalyst continuously under irradiation of UV light??? If yes, how??? If No, then the reaction mixture would not be homogeneous…..

2. How did the authors determine the concentration (ng/g) of PAHCs in soil? It must be explained clearly in the materials and methods section.

3. The introduction can be further improved with reference to the following literature.

 

https://doi.org/10.1016/j.ijheatmasstransfer.2024.125645 https://doi.org/10.1016/j.jmst.2019.09.018  https://doi.org/10.1016/j.envres.2022.112975 https://doi.org/10.1002/adfm.202307230 https://doi.org/10.1016/j.jhazmat.2023.132518 https://doi.org/10.1016/j.fuel.2023.127921 https://doi.org/10.1016/j.jcis.2023.08.033 https://doi.org/10.1016/S1872-2067(23)64566-8 https://doi.org/10.1016/j.arabjc.2022.103732  

Comments on the Quality of English Language

Minor editing needed. 

Author Response

Previous comments

R3

Top of Form

Yes	Can be improved	Must be improved	Not applicable
Does the introduction provide sufficient background and include all relevant references?	( )	( )	(x)	( )
Is the research design appropriate?	( )	( )	(x)	( )
Are the methods adequately described?	( )	(x)	( )	( )
Are the results clearly presented?	( )	( )	(x)	( )
Are the conclusions supported by the results?	( )	( )	(x)	( )

Comments and Suggestions for Authors

1. Line 63-68: “Using photocatalytic decomposition of polycyclic aromatic hydrocarbons under UV light in the presence of some semiconductor materials (FeCL3)”. FeCl3 is not a semiconductor material.

Response: As we have revised the whole manuscript the change now appear on page no 1 line 13, page no. 3 line 103, page 5, line 184. The word semiconductor is omitted and where possible the word ‘iron catalyst’ is used.

2. Four chemical reactions have been written for the production of OH radical. None of the reactions involve irradiation. However, in the text a term UV light has been used for it.

The new and corrected chemical equations are added on page 3, line no 104, 111, 112

3. Line 73, “The cathode is the target of H2O2, in contrast…………’” It is meaningless and an awkward statement.

This line/statement has been deleted.

4. Line 75, “Mechanism Fenton process doing decomposition of organic compounds via oxidation …………” Meaning less and awkward sentence.

The sentence has been deleted and replaced by the actual study mentioned via citation.

5. Similarly, the English of Introduction section upto the end is awkward. The English is not acceptable.

The overall English language of the manuscript has been revised. New and relevant data comprising l

6. Line 114-135; All the sentences are meaningless and awkward.

English language has been revised and sentence structures are rechecked.

7. Figure 3 and Figure 4; what are the units on x-axis and y-axis?

 The units are now added on the x and y axis in figures.

8. Overall, the English is very poor. This paper is not suitable for publication in Catalysts.

The whole manuscript is revised with special focus on English language and sentence errors.

 

Comments on the Quality of English Language

English is not acceptable.

Submission Date

03 June 2024

Date of this review

10 Jun 2024 09:06:20

Bottom of Form

© 1996-2024 MDPI (Basel, Switzerland) unless otherwise

 

 

R3

 Comments and Suggestions for Authors

1. The photocatalytic treatment method is not clear. Did the authors agitate/mix the soil sample and catalyst continuously under irradiation of UV light??? If yes, how??? If No, then the reaction mixture would not be homogeneous…..

Response:

2. How did the authors determine the concentration (ng/g) of PAHCs in soil? It must be explained clearly in the materials and methods section.

The determination of concentration of PAHs in the soil is added in detail on 10 line no 345-353

3. The introduction can be further improved with reference to the following literature.

 https://doi.org/10.1016/j.ijheatmasstransfer.2024.125645 https://doi.org/10.1016/j.jmst.2019.09.018 https://doi.org/10.1016/j.envres.2022.112975 https://doi.org/10.1002/adfm.202307230 https://doi.org/10.1016/j.jhazmat.2023.132518 https://doi.org/10.1016/j.fuel.2023.127921 https://doi.org/10.1016/j.jcis.2023.08.033 https://doi.org/10.1016/S1872-2067(23)64566-8 https://doi.org/10.1016/j.arabjc.2022.103732 Comments on the Quality of English Language Minor editing needed

The introduction section is improved by reading the above mentioned papers. The added text is in red color on page 2 line 88 to 98

 

 

 

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

the authors have not replied my comments at all. It is so simply. It should be rejected.

Author Response

R4

(x) I would not like to sign my review report
( ) I would like to sign my review report

Quality of English Language

( ) I am not qualified to assess the quality of English in this paper
( ) English very difficult to understand/incomprehensible
( ) Extensive editing of English language required
(x) Moderate editing of English language required
( ) Minor editing of English language required
( ) English language fine. No issues detected

 

	Yes	Can be improved	Must be improved	Not applicable
Does the introduction provide sufficient background and include all relevant references?	( )	(x)	( )	( )
Is the research design appropriate?	( )	(x)	( )	( )
Are the methods adequately described?	( )	(x)	( )	( )
Are the results clearly presented?	( )	(x)	( )	( )
Are the conclusions supported by the results?	( )	(x)	( )	( )

Comments and Suggestions for Authors

1. Please provide a more quantitative abstract.

Response: The abstract has been revised and quantitative results outlining the concentration of studies PAHs are now added. The changes are made on page no. 1 line no 16-22. The new text is in red color

2. Please add a brief illustration of the e/h production and reactive radical species in heterogeneous photocatalysis, by reading Molecules 2023, 28, 6848 and J. Mol. Struct., 2024, 1312,138501.

A new figure is added which illustrate the electron pair formation and other details in heterogenous photocatalysis. Figure no. 6

3. Pls add the DRS data, it is important.

Response: It is not applicable as we have only four carcinogenic PAHs compounds

4. The effects of the scavenging agents should be done.
5. Please deeply revise the English language level.

The English language and sentence structure is improved in the whole manuscript.

6. Please improve the resolution of Fig. 1.

Response: The resolution of the image is improved and new image is present on page no 4

7. The author should carefully review the manuscript for formatting and punctuation throughout. Such as FeCL3 should be FeCl3

The whole manuscript is rechecked and the FeCL3 is changed into FeCl3. The change occurs at 30 places at various pages and line no.

8. The catalyltic part should be illustrated in detail.

In the discussion section, studies related to the catalysis process are added which tend to explain the formation of radicals during fenton reaction. Oxidation and reduction processes are also improved to maximum extend. Please see page no 9 line 245-270

The catalytic procedure is included in the form of figure as well and added in the manuscript as figure no. 6.

 

Comments on the Quality of English Language

revised in detail

Submission Date

03 June 2024

Date of this review

07 Jun 2024 04:32:37

 

 

 

Previous comments:

 

R4

Comments and Suggestions for Authors

the authors have not replied my comments at all. It is so simply. It should be rejectedeven

Please note all required comments applied to the Round4 Manuscript

Author Response File: Author Response.pdf