A Kinetic Study on the Preparation of Al-Mn Alloys by Aluminothermic Reduction of Mn3O4 and MnO Powders
and Alfredo Alan Flores SaldÃvar 3
Round 1
Reviewer 1 Report
The introduction provides a clear overview of the study's objective and the challenges associated with aluminothermic reduction in manganese compounds.
The manuscript briefly mentions the technique of addition of powders with mechanical agitation, but it lacks sufficient details regarding the experimental setup and procedure.
It would be helpful to provide more detailed information on the intermediate oxidation states of manganese during the reaction process and their significance in forming the final Al-Mn alloys.
Author Response
The authors appreciate the reviewer’s comments which help to enhance our paper in this second submission. The attached document describe a list of all corrections attending their comments and suggestions.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This article discusses a study on the aluminothermic reduction of manganese compounds to prepare Al-Mn alloys. The researchers aimed to determine the activation energy values and reaction rate constants of the process using melting aluminum found in beverage cans and the technique of addition of powders with mechanical agitation. The kinetics of the reaction were studied under various conditions, including temperature, degree of agitation, and initial concentration of magnesium in molten aluminum. The results suggest a reaction mechanism in stages, where manganese passes through oxidation states until reaching an oxidation state for being dissolved in the molten aluminum, forming alloys with up to 1.5 wt.% of Mn. This study provides insights into the operant reaction mechanism of aluminothermic reduction and its potential application in alloy production.
The article provides valuable insights into the operant reaction mechanism of aluminothermic reduction and its potential application in alloy production, specifically in preparing Al-Mn alloys. The study identifies the operational variables that directly influence the rate of aluminothermic reduction of manganese compounds and suggests a reaction mechanism in stages, which can help optimize the process for efficient alloy production. Therefore, the article should be published as it contributes to the understanding of aluminothermic reduction and its practical applications.
You have certainly received interesting results. However, their presentation is not clear enough and understandable.
1. The first part of the article is quite clear, the conclusions are obvious. Not so with the second part, where you move on to kinetic measurements (starting on line 284). Firstly, it would be good to structure the article and separate the experimental part with the evaluation of the optimal parameters of the reaction from the part with the calculation of kinetic parameters. Secondly, there is not even a brief discussion of the considered mathematical models. They must be described before proceeding with the comparison with your experimental data. Figures 12 and 13 show points - experimental data, and curves - calculation data in accordance with mathematical models? Why such an exact match? How can you see that the kinetic measurements were in good agreement with the Jander equation, and not with other models?
2. Next, you can select the part with the definition of the activation energy (starting from line 327). You very briefly cited Figure 15. Why are only these two types of reactions considered (only with this magnesium content)? It would be possible to give a table with a number of calculated values of the activation energy for the cases you have considered.
3. Next, starting at line 334, there is a discussion of reaction mechanisms. This part can also be separated into a separate subsection. It seems to me that the discussion of reaction mechanisms is not sufficiently supported by the results that preceded in the article. You state the sequence of reaction steps, but how can this be confirmed? Or is this discussion not related to previous results at all?
4. What you have provided in the Conclusions section can be seen as a further discussion of the reaction mechanisms. It seems to me that here you should briefly summarize your achievements: the results of the experiments, which kinetic model corresponded to the experimental data, which activation energy estimates were made, and, finally, which reaction mechanisms were revealed.
5. And, finally, a small remark. Figures 4 and 5 - the caption for the figure does not match what is shown in the figure. What is the initial concentration of Mg - 3 or 1%? What is the stirring speed - 250 or 300 rpm?
Author Response
The authors appreciate the reviewer’s comments which help to enhance our paper in this second submission. The attached document describe a list of all corrections attending their comments and suggestions,
Author Response File: Author Response.pdf
Reviewer 3 Report
The scientific article "Preparation of Al-Mn alloys starting from the aluminothermic reduction of Mn3O4 and MnO; reaction kinetics and operative reaction mechanisms" is a thorough study of the processes associated with the aluminothermic reduction of manganese oxides (Mn3O4 and MnO), which play an important role in the production of metallic manganese and various manganese alloys.
The authors have done a lot of work, but it is necessary to correct the following comments:
1. In the title “Preparation of Al-Mn alloys starting....”, although there is no talk about obtaining an Al-Mn alloy in the article itself and in the conclusion.
2. It is necessary to expand the annotation, keywords, list of references.
3. For the statement “The affinity of these elements for oxygen is higher than other elements since the reactions of these with oxygen are dominant due to their negative values found in each element Gibbs free energy.” a link to the source of this information is needed.
4. It is necessary to structure the results correctly in the article. Divide the second paragraph of the article into “Analysis”, “Materials and reagents”, “Methods of conducting experiments”.
5. Item 3 also needs to be divided into several subsections.
6. The English language in this article should be checked by a native speaker for grammar.
7. Conclusions should be expanded and specified taking into account the scientific results obtained.
Author Response
The authors appreciate the reviewer’s comments which help to enhance our paper in this second submission. The attached document describe a list of all corrections attending their comments and suggestions.
Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
Dear colleagues, you have done an excellent job of improving your manuscript. The authors made the necessary adjustments and corrections, improving the quality of the manuscript. I recommend it for publication.
