Review Reports

Round 1

Reviewer 1 Report

The review must be improved by taking into consideration the following major and minor remarks:

Page 2 lines 54-55 : the sentences need clarification. How air can contribute to the formation of AMD?

Page 2 line 55 to 66 : the AMD's formation process is unclear. it is necessary to clarify and present the chemical reaction.

Page 2 : the objective of the review need more clarification and need more details.
in line 87: the sentence “mechanisms of the removal of HMs from various NMs” can causes a confusion about the objective of the review.   

Page 3 : Figure 1: it is necessary to describe if this figure presented treatment process of soils or of water or of both.
This remark confirms that the objective of the paper must be clarified, in which it must be said, if the review is interested in the treatment of soils or waters or both.

Page 3, line 118: the figure 2 cited in the text in the page 3, but it was presented in the page 8, why?

Page 4 : It is necessary to present the details of flowing abbreviations for the first time:
line 123 : nZVI
line 130 nZVI NPs
line 149 : TCR and DDT
line 150 : CMC

Page 5 : The title of the table 1 need to be clarified to describe clearly there content.

Page 9, line 339: It is necessary to be sure, if you mean AMD or just “mine drainage”. There is a big difference between the two expressions.

Page 9, line 347: the title (4.3) must be transferred to next page (page 10).

There is no informations presented about the risks related to the use of NMs, us a tools for decontamination, on the ecosystems or on the environment.

Author Response

We appreciate you for your precious time in reviewing our paper and providing valuable comments. It was your valuable and insightful comments that led to possible improvements in the current version. The authors have carefully considered the comments and tried their best to address every one of them. We hope the manuscript after careful revisions meet your high standards. The authors welcome further constructive comments if any.
Please see the attachment for point-by-point responses. 

Author Response File: Author Response.pdf

Reviewer 2 Report

Generally, this review paper comprehensively states the potential use of nanomaterials in remediation of mine drainage and soils contaminated with heavy metals.

L32. What does “high density and non-biodegradable” mean? Authors use the term biodegradable for the nature of heavy metals throughout the manuscript. This term seems not to be appropriate because metals cannot undergo “degradation” reaction.

L62. Is it Acidithiobacillus ferrooxidans?

L64. Please state concretely about how such bacteria produce acidity or catalyze the acid production.

L114. Please state concretely about “most of them” technologies.

L114. What is the secondary waste?

L117. Why do authors consider that phytoremediation and nanoremediation are the most promising tools? Please state the reason here.

L123. What is nZVI?

L144. “(CMC)” should be inserted between the terms “cellulose” and “stabilizer”.

L174-180. This paragraph seems not to be associated with remediation of heavy metals. Authors should show the association clearly.

L276 and 294. As⁺⁵ and As⁺³ should be As⁵⁺ and As³⁺.

L132. Does this report (Su et al.) show the disadvantage of nZVI for use in AMD remediation? If so, it seems inconsistent with the authors contention.

Author Response

We appreciate you for your precious time in reviewing our paper and providing valuable comments. It was your valuable and insightful comments that led to possible improvements in the current version. The authors have carefully considered the comments and tried their best to address every one of them. We hope the manuscript after careful revisions meet your high standards. The authors welcome further constructive comments if any.
Please see the attachment for point-by-point responses. 

Author Response File: Author Response.pdf

Reviewer 3 Report

There are many reviews on nanoparticle/nanomaterial technology available in the recent literature covering much of the same information as this manuscript. Infact, I have found three published in the last two years  (examples included below)

- https://doi.org/10.1016/j.enmm.2022.100679 (Nanoparticle assisted environmental remediation: application, toxicological implications and recommendations for a sustainable environment).

-https://doi.org/10.1016/B978-0-12-822401-4.00029-5  (Nano particles in remediation: strategies and new challenges.

- DOI: 10.3390/molecules23071760 Nanotechnology for environmental remediation: materials and applications.

- https://doi.org/10.3389/fenvs.2021.793765 Nanoremediation: Nanomaterials and Nanotechnologies for Environmental Cleanup

Whilst the science presented in this review is reasonable and up to date, I do not feel that the authors have made their case for this being an original or timely contribution to the academic literature, neither do they offer a unique perspective of the subject. It is largely repetition of what is available in the literature already. 

There is also considerable jumping around within the subject. A general title is given but the focus quickly narrows to acid mine drainage type scenarios. The authors would be better to review a specific topic well (e.g. nanomaterial to treat acid mine drainage) that a broad topic in a less rigorous way. 

Resolution of the figures is not good enough for publication.

 

Author Response

We appreciate you for your precious time in reviewing our paper and providing valuable comments. It was your valuable and insightful comments that led to possible improvements in the current version. The authors have carefully considered the comments and tried their best to address every one of them.

As per the valuable suggestion received, the authors wish to propose the following title in lieu of the content of the manuscript and would be glad if the title could be changed.

Proposed Title: Sustainable use of nano-assisted remediation for mitigation of heavy metals from contaminated soils and mine spills

We hope the manuscript after careful revisions meet your high standards. The authors welcome further constructive comments if any.
Please see the attachment for point-by-point responses. 

Author Response File: Author Response.pdf

Reviewer 4 Report

Even if the work is not completely innovative, undoubtedly this review is well written and adding important knowledge in the field of environmental engineering. The manuscript is suitable for publication only after revision.

1.     A lot of similar review has been reported. Please explain the improvement compared with the previous review.

2.     The references used in the review are too old to indicate the latest research in this field.

3.     2.4. Rhizodegradation of Heavy Metals: The author should introduce this part according to the specific research situation.

4.     It is not clear what makes the present study unique. Several relative papers are suggested to be cited. (10.1016/j.jhazmat.2021.128062, 10.1016/j.clay.2018.12.017).

5.     Other Problems: (a) The language needs to be further improved. (b) The resolution of all pictures should be improved.

Author Response

We appreciate you for your precious time in reviewing our paper and providing valuable comments. It was your valuable and insightful comments that led to possible improvements in the current version. The authors have carefully considered the comments and tried their best to address every one of them.

We hope the manuscript after careful revisions meet your high standards. The authors welcome further constructive comments if any.
Please see the attachment for point-by-point responses and the list of latest references cited in the manuscript. 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

All comments requested have been considered to improve the paper.

Reviewer 4 Report

Accept in present form