Bastnaesite, Barite, and Calcite Flotation Behaviors with Salicylhydroxamic Acid as the Collector

Round 1

Reviewer 1 Report

Dear authors,

The paper presents the experimental data on flotation of bastnaesite, barite, and calcite with salicylhydroxamic acid.
Title: Flotation behaviors of bastnaesite, barite, and calcite with salicylhydroxamic acid as the collector
“…Flotation behaviors…with saicylhydroxamix acid…”?
The readers will appreciate if the authors introduce slight corrections of the title and paraphrasing to make it clearer and stronger.

Line 41: …Mongolia
Maybe "Inner Mongolia"?

Lines 43 and 44: There is no coherence between ideas stated in sentences (lines 43 and 44).

Line 45: …acidor sodium oleatecan be used…
It is hard to understand the terminology and the meaning.

Lines 49, 50: …the major gangue minerals are barite, calcite, fluorite, and quartz [14]. It should be pointed out that these calcium-bearing minerals have similar chemistry…
Calcite and fluorite are the calcium minerals while quartz is not.

Lines 67-69: ...To our best knowledge, althoughthe flotation behaviors of bastnaesite using salicylhydroxamic acid (SHA) as the collector have been researched, it is interesting to note that the flotation behaviors of gangue minerals, calcium-bearing minerals, such as barite and calcite, are still to be explored.

It would be better to underline the importance of investigating of flotation behavior of gangue minerals, rather than refer to the lack of experience.

Lines 73-74: …the floating nature…
The paper will benefit if the authors use professional terminology.

Line 80: …repeated purificationby gravity and magnetic separation…
The procedures and grammar need explanation and correction.

Line 107: …deionized water…
It is not quite clear for the readers why the deionized water was used in the experiments.

Line 109: …hitch groove flotation cell…
It is not clear for the readers the meaning of the phrase.

Lines 114-116: The paper will benefit if the authors provide information on dosages of the reagents.
Providing the accuracy of measurements would be also appreciated by readers.

Line 125: …the zeta potential was measured 3 times and the average value was taken as the final result.

The paper will benefit if the authors provide the accuracy of measurements.

Lines 130 – 133: The purified mineral particles (2.0 g) were placed in a Plexiglas cell with H2SO4 or NaOH as pH regulating reagent. The purified samples were conditioned for another 3 min with SHA. Subsequently, the solid samples were washed three times using the ultrapure water with the same pH value.

It is not quite clear for the readers what pH of solutions was in the FT-IR analysis. More importantly, how the authors relate FT-IR to zeta-potentials studies (lines 194 – 198).

Line 151: …floatability of bastnaesite is better than that of barite, and calcite…
However, at pH <4 and pH>10, the recovery of bastnaesite is the lowest.

Lines 151-158:
In figures 4 and 5 some line graphs (blue and red) demonstrate similar trends, however, the authors comment on them in a different way.

Line 169: “…grate adsorption…”
The phrase has no sense and hence it is hard to understand the sentence.
In figures 4 and 5 some line graphs (blue and red) demonstrate similar trends, however, the authors comment on them in a different way.

Line 208: …concentration was 1×10-4 M… and line 212 (1×10-5 M.
It is better to clarify the reasons for choosing these (SHA and metal ions) particular concentrations.

Lines 212, 213: …The deposit pH…
It is hard for the readers to understand the meaning of the phrase.

Figure 9:
It would be better for the paper if the readers can understand which software was used to calculate and draw the logarithmic diagrams.

Line 233: …transformation of the chemical environment on these minerals surface…
It is better to paraphrase the sentence for the sake of clarity.

Lines 238–240:…According to the experimental results and analyses,SHA can be chemisorbed on the bastnaesite surface and enhance the floatability of bastnaesite; the interaction between SHA and barite, and calcite is mainly physical adsorption…

In the discussion section, it would be beneficial for the paper if the authors compared the results with recent advances on a topic.

Figure 10:
The SHA interaction with bastnaesite surface (Figure 10) is oversimplified. It is also unclear why the figure was added as there is information on the mechanism in the text.
In general, the paper can add value in the field of flotation after correction.

 

Regards,

Reviewer

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

This paper describes a straightforward study of the flotation of bastnaesite and the gangue minerals barite and calcite. I have proposed a significant number of edits (see attached PDF) but will only outline some of the comments here. There are further comments in the text which should also be addressed.

1) Page 2 line 69: barite is not a calcium containing mineral.

2) There is no need to give Figures 2 and 3 as they provide no further information than that already given in the text.

3) The authors discuss adsorption of SHA onto the Helmholtz plane of the mineral surfaces. The zeta-potential measurements do indicate interactions of the minerals with SHA but the nature of the interaction and the location of the SHA cannot be deduced from the measurements. Moreover, different double-layer theories propose differing layers. It would be better if the mention of the Helmholtz plane was left out.

4) The assignment of specific FTIR wavenumbers would be better done in Table format rather than by text. This would also make any shifts occurring on SHA adsorption clearer.

5) Figures 7 and 8 should be combined into one Figure.

6) What is the relevance of the solution calculations to explaining the FTIR analyses?

6) Page 8 lines 213. The authors talk about the "deposit pH" but what this is is not clear.

7) Discussion: The shifts in BE of XPS provide evidence of electronic perturbation which may be due to changes in chemical bonding. This should be more carefully worded.

7) Conclusion (3) is too definite considering the evidence provided. Thus should be reworded to indicate that these interactions are 'proposed' not 'definitive'. Is there any difference between the interaction of the charged species on bastnaesite and the physical interaction proposed for calcite and barite? This should be clarified.

8) The authors should also carry out flotation tests with all three minerals present both as  the purified minerals and the actual ore. The point of the study is to examine the separation of bastnaesite from calcite and barite this has not actually been done. (Note: this point is not in the attached PDF)

 

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf