Recovery of Apatite from Magnetic Concentration Tailings by Flotation
Round 1
Reviewer 1 Report (Previous Reviewer 3)
Comments and Suggestions for AuthorsAbstract:
This section was well written. However, a clear brief of the method should be provided.
1. Introduction
This section was revised as suggested comment
2. Materials and methods
This section has been revised accordingly. However, the author should show the connection between pure sample of natural calcium phosphate crystals were obtained from the Los Molles mine of Minera del Pacífico Company in Huasco, Atacama Region, Chile in line 79 and 80 with the tailing from e "El Trigo" deposit of the same company in line 85 and 86.
3. Results
This section was well written. First, the author should not only describe on textual explanations on the table 1, 2, and 3 individually. The author should mention the link or relation between them. Second, for Figure 7, the author should add results for Grade and recovery of P2 O 5 for each of the stages.
4. Conclusions
This section has included the main points.
References
Please check all the reference numbers. For instance, why there are double of numbers for the reference (1. [1])
Author Response
Dear Editor
Attach the corrections indicated in this second revision and the corrected work with the modifications indicated in red.
As all the indicated corrections have been complied with, on this occasion and previously, I hope that this time it will be published to cancel the stipulated value and will not be returned again with new corrections.
Can you tell me if, due to the cancellation of the work edition, you will send me a document that supports the payment made.
Sincerely Yours
Dr. Luis Valderrama
Author Response File: 
Author Response.pdf
Reviewer 2 Report (Previous Reviewer 1)
Comments and Suggestions for AuthorsThe manuscript organization is okay. The topic is relevant to mineral processing and environmental science. There are major comments for this version:
1. Lines 38-39: Replace with “In Chile,”. However, is it possible to generalize the size of the tailings in the whole country? Or is the size for a specific operation?
2. Lines 43-44: Are these coordinates necessary?
3. Line 48: Subscripts.
4. Line 53: What is the value of this minimum?
5. Lines 59: What are the effects on flotation of the non-soluble calcium carboxylate?
6. Lines 62-63: This sentence is not clear.
7. Introduction should be more comprehensive. Please review some previous studies on the flotation of tailings to recover apatite. Are there other regions of the world where apatite has been recovered from tailings? If there are no studies, please clearly indicate it. However, indicate some of the minerals that are widely recovered from tailings. Therefore, the novelty of your work will be clearer.
8. Line 81: Tailings already have been passed through size reduction, did you further grind?
9. Section 2.1: Are the tailings aggregated with soil or trapped in insoluble materials? Once the tailings are added in water, do they dissolve?
10. Lines 95-96: Did the authors conduct similar work to this manuscript? The novelty can be hindered.
11. Line 148: Full name.
12. Figure 2: Font size in the legend is very small.
13. Line 177: This statement needs to be revised. Electrostatic interactions between particles and bubbles have an impact on the attachment. What is the zeta potential of the bubble at flotation pH 10? It should be higher than -25 mV, which results in a high repulsive interaction. According to the XDLVO theory, only the high contact angles in Figure 2 can result in successful attachments after collisions. Therefore, Atrac is not the best because of the zeta potential but because of the contact angle. If possible, please calculate the XDLVO profiles.
14. Lines 178-180: This sentence is not clear.
15. Line 190: What do you mean by buoyancy?
16. Lines 194-195: “this study is a technical work” should be removed.
17. Lines 208-209: Are there references to support this statement?
18. Line 233: Please add the reference number.
19. Lines 235-237: Please briefly describe what the difference in k means.
20. Figure 6: Please add error bars to the symbols. The model used to draw the lines should be indicated in the caption.
21. Section 3.3: Please indicate the methodology used to conduct the simulations. Any software or model?
Author Response
Dear Editor
Attach the corrections indicated in this second revision and the corrected work with the modifications indicated in red.
As all the indicated corrections have been complied with, on this occasion and previously, I hope that this time it will be published to cancel the stipulated value and will not be returned again with new corrections.
Can you tell me if, due to the cancellation of the work edition, you will send me a document that supports the payment made.
Sincerely Yours
Dr. Luis Valderrama
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report (Previous Reviewer 1)
Comments and Suggestions for AuthorsI do not have comments for this revision.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsCharacterization and flotation kinetics were provided. Conclusions are supported by the results. There only minor revisions:
Line 29: What country?
Lines 29-31: References are required.
Lines 36-38: The typical range of particle size is required. This is additional to your range in Figure 1.
Lines 39-57: What are typical estimated grades in tailings of the material in question? What pros and cons does the grade introduce in flotation?
Line 66: Does this collector belong to fatty acids? How is it different from fatty acids?
Line 76: Since you reported the zeta potential, it should be zeta potential measurements instead of electrophoretic mobility tests.
Line 104: rpm and aeration rate should be provided. Is it a self-aeration system?
Lines 151-156: Error bars must be provided in Figure 2. ANOVA analysis is required to objectively confirm statistical differences between means. This will quantitatively show that atrac 2600 indeed improved the contact angle.
Figure 3: Error bars are required.
Lines 162-174: At pH 10, the zeta potential of the mineral with atrac 2600 is highly negative. Bubbles at this pH, and considering the frother, have a charge of approx. -30 mV, which is highly unfavorable for bubble-particle interactions. Consequently, the contact angle becomes critical to overcome the unfavorable interactions. Therefore, this paragraph must be revised. Note Particle–bubble interaction energies for particles with physical and chemical heterogeneities.
Figures 4 and 5: Error bars are required.
Reviewer 2 Report
Comments and Suggestions for AuthorsOverall, Article may need to correct some details.
This article is more like a report of working data than a research report. In the first chapter, the author explains that the article focuses on evaluating the performance of the new synthetic collector Atrac 2600 in topic of apatite grade and recovery. However, in the discussion part of the article, the author did not show the molecular structure and chemical properties of the agent, nor did he show the changes in the properties of the mineral surface before and after the action of the agent. Only with Zeta potential test information and flotation data, we cannot clearly know the mechanism of action between agents and minerals, let alone provide conclusions that can be used for reference by other research. In addition, the structure of the article is not reasonable, and the data of the experimental samples should be presented in the second part "Materials and Methods". In the second part "Materials and Methods", the author's explanation of "Materials and Methods" is confusing. We cannot distinguish between flotation experiments that study the properties of the reagents and those that test the plausibility of laboratory-scale flotation protocols.
Comments for author File: Comments.pdf
Extensive editing of English language required
Reviewer 3 Report
Comments and Suggestions for AuthorsThis manuscript presents a study on the recovery of apatite from magnetic tailings generated at the Minera del Pacífico Company, Chile. While the work holds relevance for the industrial field, its academic soundness appears to be limited. To enhance the manuscript's quality, the author should consider restructuring the overall content for better coherence and rigor.
Abstract:
Introduction: The introduction lacks proper organization. To captivate the reader's interest, the author should incorporate more information regarding the geology and reserves of iron oxide-apatite ore in del Pacífico Company, Chile. Additionally, providing details about the amount of tailings or the production rate will enhance the understanding of the significance behind undertaking this study.
Check line 91; Please revise “y 1x10-5”
Materials and Methods: This section requires better organization and structure. I highly recommend the author to restructure it accordingly. To enhance clarity, the study on pure apatite should be separated into the subsection, followed by the flotation of tailing contaning apatite, and finally, the kinetic study. The section should be divided into four subsections: "Sample Preparation," "Flotation of Pure Apatite," "Flotation of Apatite-Containing Tailings," and "Flotation Kinetics." This revised arrangement will ensure a more logical flow of information and improve the overall presentation of the content.
In addition: The author must provide a rationale for selecting sodium oleate and Atrac 2600 as collectors in this study.
Results: This section lacks proper organization. I recommend the author to restructure this section and follow it with "Materials and Methods" for better clarity and coherence.
