Options for Increasing the Rate of Bioleaching of Arsenic Containing Copper Concentrate
Round 1
Reviewer 1 Report
1) The present manuscript is a valuable one in terms of the difficult to treat arsenic-containing minerals albeit containing significant valuable metals and more often gold a s well. Therefore, the study can be good enough to include in microbiology research after a minor revision as suggested below.
2) The introduction needs to be revised in more structured manner by including a systematic discussion on the types of arsenic minerals present and the existing issues for their processing. Additionally, the contamination of arsenic should also be defined to show the environmental issue with the existing processes and then the research hypothesis for a need of microbial solution can be drawn.
3) I would like to suggest for the inclusion of recently published articles on arsenic-containing minerals and their microbial treatment such as, 10.3390/min10110972; 10.1016/j.ibiod.2020.105042; https://doi.org/10.1016/j.biortech.2020.123181
4) In tables 1 and 2: how the authors analyzed the fraction of sulfur species? It should be discussed in the experimental section.
5) It is a common practice in biological system, the error bar should be included to show the repeatability of experimental data. Also, it should be clarified that whether the authors themselves checked the repeatability or not. If not then they should check and then the data in error bar should be represented in all the illustrations.
6) Discussion section should be improved more in a scientific manner.
7) Conclusion section is very weak. It should be re-constructed.
Author Response
Reviewer 1
The present manuscript is a valuable one in terms of the difficult to treat arsenic-containing minerals albeit containing significant valuable metals and more often gold a s well. Therefore, the study can be good enough to include in microbiology research after a minor revision as suggested below.
Authors are grateful to the Reviewer for evaluation of the work. Please, find our answers below:
Comments and Answers:
- The introduction needs to be revised in more structured manner by including a systematic discussion on the types of arsenic minerals present and the existing issues for their processing. Additionally, the contamination of arsenic should also be defined to show the environmental issue with the existing processes and then the research hypothesis for a need of microbial solution can be drawn.
The introduction was improved and structured.
- I would like to suggest for the inclusion of recently published articles on arsenic-containing minerals and their microbial treatment such as, 10.3390/min10110972; 10.1016/j.ibiod.2020.105042; https://doi.org/10.1016/j.biortech.2020.123181
Additional references were included.
- In tables 1 and 2: how the authors analyzed the fraction of sulfur species? It should be discussed in the experimental section.
Information was added.
- It is a common practice in biological system, the error bar should be included to show the repeatability of experimental data. Also, it should be clarified that whether the authors themselves checked the repeatability or not. If not then they should check and then the data in error bar should be represented in all the illustrations.
Experiments in the study were performed in single as long term labor-consuming experiments were performed using large-volume laboratory scale reactors. Therefore, diagrams showing results of batch experiments do not contain error bars (Figures 1 and 2). In the same time, Table 3 showing results of continuous experiments includes errors since average results based on the analysis of several samples collected during long-term experiments in pseudo steady state.
- Discussion section should be improved more in a scientific manner.
Discussion was improved.
- Conclusion section is very weak. It should be re-constructed.
Conclusion was improved.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Paper entitled “Options to increase the rate of bioleaching of arsenic containing copper concentrate” meets the necessary standards for publication in this journal.
Please check the entire manuscript carefully for eventual typographical errors.
Attention when writing references. They are not unitary.
Final Conclusion: The paper meets the necessary standards for publication.
Author Response
Reviewer 2
Paper entitled “Options to increase the rate of bioleaching of arsenic containing copper concentrate” meets the necessary standards for publication in this journal. Please check the entire manuscript carefully for eventual typographical errors. Attention when writing references. They are not unitary.
Final Conclusion: The paper meets the necessary standards for publication.
Authors are grateful to the Reviewer for evaluation of the work. Please, find our answers below:
Comments and Answers:
- Please check the entire manuscript carefully for eventual typographical errors.
The manuscript was checked and typographical errors were сcorrected.
- Attention when writing references. They are not unitary.
The references were checked and errors were corrected. Also, several references were added.
Author Response File: Author Response.docx
