Selective Adsorption of 2-Hydroxy-3-Naphthalene Hydroxamic Acid on the Surface of Bastnaesite and Calcite
Round 1
Reviewer 1 Report
Dear Authors,
Although the paper has a potential for publishing, it needs revision. I am afraid it is hard to understand the meaning of the paper in the current form.
Please check the Introduction section for symbols and words that apper occasionally, e.g.:
Lines 29,30 : ...and heavy REEs Error! Reference 29 source not found.2.
Line 40: ...gangue mineral is different 910.
Pleas, pay attention to the names of sections 4. Conclusions and 5. Conclusions.
Also, readers appreciate if authors provide the samples masses in both pure minerals and mixed ore flotation, and number of replicas.
Finally, it might be beneficial to add a table summarizing the results of IR and XPS tests, containing essential information for specific minerals, bonds, and compounds describing in the Results section. On the same note, maybe to simplify a detailed description of IR, XPS, etc. or to place them in the Discussion section. A separate Discussion section will be appreciated by readers.
Regards,
Reviewer
Author Response
Thank you for your valuable suggestions, which will be very helpful for our follow-up research. Any questions, please feel free to contact us, I would be very grateful.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This manuscript performs a comparative investigation of the performances of 2-hydroxy-3-naphthalene hydroxamic acid (NHA), salicylhydroxamic acid (SHA) and sodium oleate (NaOl) for the flotation separation of bastnaesite and calcite. This is a meaningful study. While this manuscript needs professional English editing before being accepted. Four problems are addressed as follows.
Q1. The title of this manuscript needs to be revised. Some examples are provided for reference “Selective adsorption of 2-hydroxy-3-naphthalene hydroxamic acid on the surface of bastnaesite and calcite”, “Interaction mechanism of 2-hydroxy-3-naphthalene hydroxamic acid in the flotation separation of bastnaesite and calcite”.
Q2. The word “bastnaesite” should be used throughout the paper. The words “fluorocerium cerium ore” and “fluorocarbon cerium ore” should be removed to avoid ambiguity.
Q3. Why doesn’t the infrared spectrum of NHA (Fig. 6a) show the characteristic peaks of the tensile vibrations of N-H and C-O at 3732 cm−1, 3672 cm−1 and 3648 cm−1? While the infrared spectrum of the bastnaesite particles treated by NHA shows the relevant characteristic peaks of NHA.
Q4. One previous study has reported the application of NHA as the collector in the flotation separation of bastnaesite and calcite. This study should be cited (Guo, Z.; Khoso, S.A.; Wang, J.; Zhang, C.; Gao, Z.; Sun, W.; Tian, M.; Liu, Y. Interaction mechanism of 2-hydroxy-3-naphthyl hydroxamic acid and 1-hydroxy-2-naphthyl hydroxamic acid in the flotation separation of bastnaesite/fluorite: Experiments and first-principles calculations. Sep. Purif. Technol. 2021, 285.).
Author Response
Thank you for your valuable suggestions, which will be very helpful for our follow-up research. Any questions, please feel free to contact us, I would be very grateful.
Author Response File: Author Response.pdf
Reviewer 3 Report
In this paper, the selective collection performance of NHA, NaOL and SHA on bastnaesite and calcite is compared, and the internal mechanism of various phenomena in the process of the experiment is studied by a variety of analytical test methods. It seems to be quite interesting. But some changes need to be made before publication can be considered. Major issues include:
1. It is mentioned in the introduction that "light REEs has unique properties", which can be briefly introduced in this part;
2. It is recommended to unify the number of significant digits or decimal places of the data in Table 1;
3. The clarity of each curve in the paper needs to be improved;
4. The expressions of "C 1 s, N 1 s, O 1 s" in Table 4 seem to be non-standard and need to be checked;
5. There is no obvious spectral peak at "3387, 1448 and 1427" in FIG. 6, but there are marks in the figure, please explain them;
6. There were "4 Conclusions" and "5 Conclusions" in the paper, please review them carefully;
7. The "5 Conclusions" section needs to be reorganized as the existing content did not reflect the important findings and results in the research process of this paper.
Author Response
Thank you for your valuable suggestions, which will be very helpful for our follow-up research. Any questions, please feel free to contact us, I would be very grateful.
Author Response File: Author Response.pdf
Reviewer 4 Report
This manuscript is an interesting development for bastaesite flotation. Although the results are interesting, I have the following comments:
1. There are plenty of studies regarding the flotation of bastnaesite. To increase the interest of the target audience, I recommend including a brief state of the art regarding the existing methodologies for flotation of this mineral, and the potential operational problems that could be resolved through the results of this study.
2. I think the manuscript, in its current form, requires more scientific discussions for a research article. I recommend including discussions regarding the chemical behavior of the bastnaesite as an ore, depending on the pH value of the solution. For this task, I send attached a study that shows the ion dissociation of the bastnaesite, for the most common rare earths included in it.
Comments for author File: Comments.pdf
Author Response
Thank you for your valuable suggestions, which will be very helpful for our follow-up research. Any questions, please feel free to contact us, I would be very grateful.
Author Response File: Author Response.pdf
Reviewer 5 Report
The manuscript deals with the interactions of two minerals using a specific collector. I recommend the article for publication after adding and explaining a few facts.
1. In the pdf format that I downloaded from the journal's website, the literature references are not displayed correctly. This is probably not the fault of the authors, on the other hand it was not possible to check this part.
2. Table 1 shows the chemical composition of the mineral bastnaesite. Are these percentages by weight? Probably yes, I recommend supplementing. The total sum of individual oxides is far from equal to 100%. Please explain. The same applies to Table 2, the chemical composition of calcite. In both cases, the item "others" appears. I would expect this to be an unspecified composition that will complement the identified items to a total of 100%.
3. Explain the discrepancy in the data in Figure 4. The percent recovery for the NaOL collector is approximately 82% at pH 9. It cannot be determined exactly from the picture. However, it is clear that the recovery is lower than the other two collectors. In the next picture, where the collector dose is monitored, under the same conditions, the recovery with the NaOL collector is practically the same as with the other two collectors. I am comparing pH 9 and collector dose 4x10-4 mol/L.
4. It would be appropriate to add information about the price of individual collectors, which is extremely important for practice.
5. At the end of the article there is a chapter "Conclusions" twice. Explain.
Author Response
Thank you again for your valuable suggestions, which will be very helpful for our follow-up research. Any questions, please feel free to contact us, I would be very grateful.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Dear Authors,
The paper has been improved significally.
Regards,
Reviewer
Reviewer 4 Report
The manuscript has improved considerably from its previous form. I recommend accepting it in its present form.
