Facile Functionalization of Charcoal by a Green Approach
Round 1
Reviewer 1 Report
The topic of this work is really interesting and novel. Nevertheless, there are several points where revision is required towards the manuscript improvement. The abstract is too short to provide the necessary information to the reader to understand properly the topic of the research, the objectives and the meaning of this study. There is not any reference to the findings of this work in the abstract. The abstract totally needs improvement and enrichment in my opinion. You would rather use the term "hemicelluloses" in plural form in the text, due to the nature of composition. The dot should be placed after the references perenthesis. Why should the word charcoal to be in capital the first letter? The same question arise for the oxygen, nitrogen etc. in the text. I propose in line 29 to add the current reference https://doi.org/10.5552/drvind.2021.2026 to support the description of the chemical changes during the increase of temperature in wood mass. In line 62, a reference is required here as well. Generally the list of references of this work could be considered rather poor if we could take into account the so far literature. In line 75, the word "increasing" needs improvement. In lines 72-76, you should provide more information respective the previous work and what has been found so far. The lines 78-80 should be combined to the previous paragraph. Please, provide some information in brief related to the fire-retardands you refer in the text (QPS etc.). In the end of introduction, it is not clearly described what the the specific study will deal with, what is the objective and generally, singificance/impact of this work. In materials-methods chapter, several crucial information is missing concerning the raw material used to produce the charcoal or if the charcoal was purchased and not prepared by the authors, the information should be provided by the producer and presented here. There are double spaces and symbols not properly presented, such as the oC not being superscript etc. You do not provide the singificant information for all the equipment used (FTIR etc.), make again a check. You do not refer anything about any statistical analysis applied in the results of this work, please explain. The discussion of the results is really short and not properly prepared. In my opinion, an image of the produced charcoal or the process of fire retardands application would be very attractive to the readership. The conclusions refer mainly the most significant findings and not the potential utilization of them, their singificance etc.Author Response
Dear Editor,
we would thank you for giving us the opportunity to revise our manuscript and for your constructive and useful comments and suggestions aimed at improving the quality and the significance of our manuscript entitled “Facile functionalization of charcoal by a Green Approach “
We have analyzed your comments and criticisms and have made several modifications that we hope will satisfy your questions and the requirements of the Journal.
The topic of this work is really interesting and novel. Nevertheless, there are several points where revision is required towards the manuscript improvement.
1)The abstract is too short to provide the necessary information to the reader to understand properly the topic of the research, the objectives and the meaning of this study. There is not any reference to the findings of this work in the abstract. The abstract totally needs improvement and enrichment in my opinion.
Thank you for your useful suggestion. The abstract was improved, stressing the aspect related to the functionalization as main topic of the paper, and some additional information about the dispersibility were added.
The text “The ability of Charcoal, a low-cost material derived from biomass pyrolysis, to provide interesting fillers with antimicrobial and flame-retardant properties is discussed here. The adducts obtained through a sustainable procedure, show a significant uptake close to 30% by weight of well-known quaternary phosphonium salts, tetraphenyl phosphonium bromide, and dodecyl triphenyl phosphonium bromide. The new fillers were characterized mainly by elemental analysis, wide-angle X-ray diffraction, infrared spectroscopy, and thermogravimetry. Additionally, a study of increasing and decreasing the ratio between the reagents for both adducts was performed to improve salt uptake and optimize the cationic exchange”
Was changed into:
“The ability of charcoal, a low-cost material derived from biomass pyrolysis, to be functionalized via cation exchange in aqueous solution providing new interesting fillers with possible antimicrobial and flame-retardant properties, is discussed here. The adducts obtained through this sustainable procedure, show a significant uptake close to 30% by weight of well-known quaternary phosphonium salts, tetraphenyl phosphonium bromide, and dodecyl triphenyl phosphonium bromide. The new functionalized materials were characterized by elemental analysis, wide-angle X-ray diffraction, infrared spectroscopy, and thermogravimetry. Additionally, a study on changing the ratio between the reagents for both adducts was performed to improve salt uptake and optimize the cationic exchange. Dispersibility tests showed the ability of functionalization to deeply change the polarities of the carbon materials to modify the compatibility and improve the possible interactions with different media, such as different polymer matrixes.”
2) You would rather use the term "hemicelluloses" in plural form in the text, due to the nature of composition. The dot should be placed after the references perenthesis.
The term hemicellulose was converted into hemicelluloses
3) Why should the word charcoal to be in capital the first letter? The same question arise for the oxygen, nitrogen etc. in the text.
The word charcoal was written as request as well as oxygen and nitrogen.
4) I propose in line 29 to add the current reference https://doi.org/10.5552/drvind.2021.2026 to support the description of the chemical changes during the increase of temperature in wood mass.
The reference was added as ref .4 as required.
5) In line 62, a reference is required here as well.
The reference related to the surface modification “Acocella, M.R.; D’Urso, L.; Maggio, M.; Avolio, R. ; Errico M.E.; Guerra, G. Green and Facile Esterification Procedure Leading to Crystalline-Functionalized Graphite Oxide Langmuir 2017, 33, 6819-6825 was added as ref 24.
6) Generally the list of references of this work could be considered rather poor if we could take into account the so far literature.
As suggested from the editor, we included recent references and the most of that are reviews, to give a rapid overview to the readers.
7) In line 75, the word "increasing" needs improvement.
In line 75 the word "increasing was changed into enhancing
8) In lines 72-76, you should provide more information respective the previous work and what has been found so far. The lines 78-80 should be combined to the previous paragraph.
The information respective the previous work were improved and the line 72-76.
“We have recently described an eco-friendly procedure for preparing cationic drug adducts with Charcoal and lidocaine, which could be suitable for cationic drug release.[24] , The adduct formation can be realized in an alkaline aqueous solution through a preliminary oxidation step that, assuring the increasing of oxygen content, provides li- docaine uptake up to 30wt% by ionic functionalization. It has to be noted that the oxida- tion step was crucial to provide high salt uptake.”
Were changed into:
“We have recently described an eco-friendly procedure for preparing cationic drug adducts with charcoal and lidocaine, which could be suitable for cationic drug release.[27] In particular, the adduct formation can be realized in an alkaline aqueous solution through a preliminary oxidation step that, assuring the enhancing oxygen content, provides lidocaine uptake up to 30wt% by ionic functionalization. It has to be noted that the oxidation step was crucial to provide high salt uptake, resulting in an efficient cationic exchange only with oxidized charcoal. Further confirmation of efficient cation exchange was obtained by UV spectra of neutral and acidic aqueous solutions showing the ability to release the drug fast and completely in both neutral and acidic conditions.”
And the lines 78-80 were combined to the previous paragraph.
9) Please, provide some information in brief related to the fire-retardands you refer in the text (QPS etc.).
Thank you for your suggestion. The sentence related to the flame retardant action of QPS
“The action mechanism of quaternary phosphonium salt is different from the usual flame-retardant action of halide compounds, being the flame-retardant function both in the condensed and gas phase. Among the several factors determining the performance of phosphorus retardation of combustion in condensed and gas phases of a specific system, such as the polymers types, the elemental phosphorus or phosphorus present in the compound, the good dispersion and interaction with the polymer matrix represent an important parameter. Therefore, the use of intercalation compounds resulting in higher dispersibility could improve flame retardant properties”
is reported on page 3 .
10) In the end of introduction, it is not clearly described what the the specific study will deal with, what is the objective and generally, singificance/impact of this work.
Thank you for your useful suggestion. To emphasize the focus of the paper about the easy and green functionalization of carbon materials, the end of introduction was implemented .
Specifically the sentence :
“Based on the interesting results previously published [30] here, we report the synthesis of the new adducts. using a straightforward green procedure base-assisted in water solution that in reduced time, assures high uptake of QPS”
Was rephrased as follow:
“Based on the interesting results previously published [30] here, we report the synthesis of the new adducts. using a straightforward green procedure base-assisted in water solution that in reduced time, assures high uptake of QPS. The reaction can be performed after a step of oxidation with hydrogen peroxide and subsequent basification in a water solution, to provide new functionalized carbon materials via cation exchange in presence of the phosphonium salts.”
11) In materials-methods chapter, several crucial information is missing concerning the raw material used to produce the charcoal or if the charcoal was purchased and not prepared by the authors, the information should be provided by the producer and presented here.
Sorry for the missing information. The charcoal was purchased and the supplier was indicated.
12) There are double spaces and symbols not properly presented, such as the oC not being superscript etc.
We removed double spaces and the possible typos present.
13) You do not provide the singificant information for all the equipment used (FTIR etc.), make again a check.
All the information related to the FTIR equipment, (instrument, detector, resolution, spectral range and scans) are reported in materials and method. Additionally, the KBr pellet preparation was added to the description.
14) You do not refer anything about any statistical analysis applied in the results of this work, please explain.
In the table of elemental analysis ad additional sentence in the table caption was added for the error bar associated to C, O and H.
15) The discussion of the results is really short and not properly prepared. In my opinion, an image of the produced charcoal or the process of fire retardands application would be very attractive to the readership. The conclusions refer mainly the most significant findings and not the potential utilization of them, their singificance etc.
To improve the discussion of the results, additional experiments were performed to show how the functionalization deeply affect the polarity and so the dispersibility of the starting materials. ( see Figure 5 on page 9 and the comments related on page 8-9)
Author Response File: 
Author Response.docx
Reviewer 2 Report
Dear Authors,
I read carefully your manuscript and in my opinion, is up-to-date and of high potential interest to readers, due to the interesting topic and non-conventional modification of charcoal. Below, please find several remarks that should be taken into account before publication:
- line 14 and 15 - I suggest saying "changes" instead of "increasing and decreasing"; same in line 258
- line 34 - in my opinion better say "pyrolysis time" instead of "slow or fast pyrolysis"
- lines 38-40, where you listed the profitable applications of charcoal, I suggest adding the following citation https://doi.org/10.3832/ifor1963-009 where the results of significant formaldehyde emission reduction due to charcoal are presented
- lines 138-140 - please provide the producer of the TGA measurement unit
- lines 179-181 - in my opinion, the significant part of this paragraph should be moved to the Methodology chapter
- table 1 - please keep the same precision when providing results (O (%) for oC/DTPP - lack of digit after the dot)
- figure 4 A - if there is no special reason to start the "Weight loss (%)" axis (vertical) from minus 10, please unify the range of axes with fig. 4 C
Best regards!
Author Response
Dear Editor,
we would thank you for giving us the opportunity to revise our manuscript and for your constructive and useful comments and suggestions aimed at improving the quality and the significance of our manuscript entitled “Facile functionalization of charcoal by a Green Approach “
We have analyzed your comments and criticisms and have made several modifications that we hope will satisfy your questions and the requirements of the Journal.
Following we address the Reviewers' comments:
Reviewer#2
Dear Authors,
I read carefully your manuscript and in my opinion, is up-to-date and of high potential interest to readers, due to the interesting topic and non-conventional modification of charcoal. Below, please find several remarks that should be taken into account before publication:
1) line 14 and 15 - I suggest saying "changes" instead of "increasing and decreasing"; same in line 258
The sentence “a study increasing and decreasing the ratio between the reagents..”
was changed into
“a study of changing the ratio between the reagents…”
In lines 14-15 and 258 as requested.
2) line 34 - in my opinion better say "pyrolysis time" instead of "slow or fast pyrolysis"
Slow and fast pyrolysis was removed and pyrolysis time was added.
3) lines 38-40, where you listed the profitable applications of charcoal, I suggest adding the following citation https://doi.org/10.3832/ifor1963-009 where the results of significant formaldehyde emission reduction due to charcoal are presented
Thank you for your comment. The article suggested was added as ref. 9
4) lines 138-140 - please provide the producer of the TGA measurement unit
Sorry for the missing information. The producer for TGA was added in materials and method.
5) lines 179-181 - in my opinion, the significant part of this paragraph should be moved to the Methodology chapter
As suggested, the sentence
“The reactions were stopped after 1h, and the products were extensively washed with 179 water to remove the residual excess salts. After drying the powders for 12h at 60 °C, the 180 mass yield was 80% for both adducts as evaluated on the total amount of oC used in the 181 reactions”
Was moved to the methodology chapter.
6) table 1 - please keep the same precision when providing results (O (%) for oC/DTPP - lack of digit after the dot)
The same precision is now reported for all the results.
7) figure 4 A - if there is no special reason to start the "Weight loss (%)" axis (vertical) from minus 10, please unify the range of axes with fig. 4 C
The range of axes was unified for figure 4C, and now the vertical axis starts from zero.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
As I have checked the authors have implemented the proposed changes in the revised verion of manuscript towards the improvement of their work. Almost all the changes have been implemented and in my opinion, the manuscript is well-prepared and organized enough to be accepted for publication in this journal. I remain at your disposal for any clarification.
