Enhancement of the Acid Resistance of Silty Clay Using Nano-Magnesium Oxide

Round 1

Reviewer 1 Report

The article definitely contains some new and interesting results that can be recommended for publication, but only after the article has been finalized and some shortcomings have been eliminated.

1. The introduction seems to be too long. The first 1.5 pages are based on rather old works, so the understanding of the relevance and usefulness of this work is lost.

2. More information about MgO, and especially nano-MgO, would be helpful, especially in light of the comparison and difference in their properties and their new applications. This will attract the attention of more readers. See for example:

Popov, A. I., Shirmane, L., Pankratov, V.,  et al (2013). Comparative study of the luminescence properties of macro-and nanocrystalline MgO using synchrotron radiation. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 310, 23-26.

Supin, K. K., et al. "Effects of calcinations temperatures on structural, optical and magnetic properties of MgO nanoflakes and its photocatalytic applications." Optical Materials 132 (2022): 112777.

Shanthi, R. Vijaya, et al. "Analysis on the combined effect of Gd3+ and Er3+ lanthanides in the microscopic, physicochemical and photocatalytic characteristics of MgO nanoparticles." Optical Materials 125 (2022): 112118.

3. How OH and point defect-free are nano-MgO and what role could it play? It is a pity that the authors did not give measurements of infrared spectra.

4. The legend in Figures 11-16 is poorly distinguishable.

 

5. The authors described all the experiments in sufficient detail, however, in the conclusions it should be clearly stated what fundamentally new data on the studied materials were obtained in this work.

Author Response

See attached file

Author Response File: Author Response.pdf

Reviewer 2 Report

The following parts of this article need to be revised:

1. The introduction chapter of the article is too long, the main problems of the current research are not prominent enough, and the main original points of this article are not clear.

2. The styles of figures and tables need to be retyped according to the materials journal.

3. Supplementary materials and other places need to be filled in completely.

4. The conclusion of the article is too long and the focus is not prominent enough. It is necessary to readjust the conclusion of this article.

Moderate editing of English language required

Author Response

See attached file.

Author Response File: Author Response.pdf

Reviewer 3 Report

In the present manuscript, the authors studied the effect of nano 2 magnesium oxide on the strength characteristics of clay soil by modifying the acid resistance of the soil. The results of the study are interesting and can have practical applications. However, I have a few comments.

The article is carelessly written. Both the table and the references are wrongly formatted. The authors did not provide all the necessary information, such as authors' contributions, conflicts of interest, etc.

The literature is also improperly cited in the manuscript. The authors should use a template for proper citation.

The authors used different kinds and sizes of fonts. It should be standardized throughout the manuscript.

In line 54 and throughout the manuscript, chemical formulas should be written using subscripts.

Conclusions should be more concise and should not be numbered.

The limitations of the study should also be included in the conclusion section.

Most importantly, I did not find any information about the statistical evaluation of the results. I did not even find standard deviations. This disqualifies the manuscript from being published in its present form.

Author Response

See attached file

Author Response File: Author Response.pdf

Reviewer 4 Report

Overall speaking, this is a very interesting study. The authors firstly showed the damaging effect of HCl on the soil engineering properties. Then, the soil stabilizing effect of MgO was demonstrated. I only have some suggestions.

1. The literature review for acid contaminated soil is good, but the stabilization part should include some recent studies about the traditional stabilizer and other new stabilizers. The soil stabilization is also often related to base stabilization. The cement treated base (CTB) is the most widely used one. Recent studies also showed the use of geopolymer stabilizer (e.g., "Evaluation of glass powder-based geopolymer stabilized road bases containing recycled waste glass aggregate. Transportation Research Record, 2674(1), pp.22-32.").

2. More information should be provided on the curing method, loading rate for compressive strength test.

3. Have you done SEM-EDS analysis? How do you know the SEM images showed M-S-H?

4. The conclusions should be more concise and only include the key findings.

Author Response

see attached file.

Author Response File: Author Response.pdf

Reviewer 5 Report

The paper presents results from experiments studying the effect of 4%, 8%, and 12% of HCl solution он the strength characteristics of silty clay soil and the possibility to improve the soil resistance by adding to the soil different amounts of nano magnesium oxide.

In my opinion this is generally well designed, carried out and presented work. Useful results are obtained, however their range of application is not particularly wide - for the specified type of soil contaminated with hydrochloric acid in relatively high concentrations

Nano magnesium oxide is not cheap - a fast internet search showed 210 - 240 USD per kg. The paper would increase its value if some comments on the price of the soil treatment are given and compared with other means/chemicals used to increase the soil strength. This my proposal is not obligatory.

Some small (mainly technical) corrections are proposed - see the attached file.  

Comments for author File: Comments.pdf

Moderate editing of English language required

Author Response

See attached file.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have successfully improved the original version of their manuscript, responding constructively to all the comments/recommendations of the reviewer.  Therefore, the article can be recommended for publication.,,

However, the authors still need to prepare reference list and corresponding citations in the text, according MDPI rules.

Author Response

 The reference list and corresponding citations in the text were prepared according MDPI rules.

Reviewer 2 Report

The authors revised the manuscript.

 

Minor editing of English language required

Author Response

The English language was edited and all errors were corrected.

Reviewer 3 Report

Dear Authors, I did not find the answers for my comments.

 

Author Response

See attached file

Author Response File: Author Response.pdf

Round 3

Reviewer 3 Report

The authors corrected the manuscript accordingly.

The authors corrected the manuscript accordingly.