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Peer-Review Record

Ion Flotation of Ytterbium Water-Salt Systems—An Innovative Aspect of the Modern Industry

Water 2021, 13(24), 3493;
Reviewer 1: Anonymous
Reviewer 2: Anonymous
Reviewer 3: Anonymous
Water 2021, 13(24), 3493;
Received: 3 November 2021 / Revised: 21 November 2021 / Accepted: 2 December 2021 / Published: 8 December 2021
(This article belongs to the Special Issue Active Contamination Event Detection in Water-Distribution Systems)

Round 1

Reviewer 1 Report

The reviewed article is an interesting study on the removal of ytterbium ions from aqueous standard test solutions by adsorptive bubble method - ion flotation. The paper is well written and organized, with a deep discussion of the results to give significance of the results found. Therefore, I recommend its publication after minor revision.


Abstract. In the abstract key findings should also be presented.

Introduction. Please reformulate/ complete the last phrase with a clear presentation of the aims of the research. It is ambiguous the meaning of “experimental and thermodynamic study”.

Materials and Methods. The information in section 2.1 is rather appropriate for the introduction section. What is the reason of indicating reference 31 (page 2 line 75) as related to the flotation machine? Please be consistent when expressing the measurement units (e.g. page 2 lines 76 and 78, mol/l and mol l-1).

Author Response

Thank you very much for your comments on my work, I tried to correct my mistakes.
Abstract. I supplemented it with key conclusions - thank you

Introduction. I moved section 2.1 to the introduction.

Materials and Methods. The reason for the reference to my work [31] is not accidental. I use a flotation machine for my experiments and I think that it is necessary to refer the work where this flotation machine is used.

Author Response File: Author Response.pdf

Reviewer 2 Report

  1. Abstract need be rewritten to show the results of this study.
  2. The title of this manuscript can be revised, to add “ion flotation” and “ytterbium cations”.
  3. The description sentences of past studies and experimental results should use the past tense.
  4. Authors used the word “one” for many times in whole manuscript, please revise it.
  5. Please check the references, 12 and 10, 32-37.

Author Response

Thank you for your comments.
1. I supplemented the abstract with the key conclusions of this work

2. I corrected the title of the manuscript by adding the words "ion flotation" and Yb

3. In sentences describing past studies, I applied the past tense

4. Thank's for this remark. I tried to delete these "one"

5. Page 1.The presence of polar points of view on the effects of REE on the human body serves as the basis for studying this area [7-11]. The paper studies the possibility of lanthanide ions removal from diluted aqueous solutions (as exemplified by yttrium ions) by ion flotation method using NaDS as collector agent [12].

Page 2 - The removal ratio of ion flotation when removing metal cations from the solutions of lean technogenic raw materials achieved 100% [30-33]. The resulting froth pulp and the solution that remained in the cuvette were analysed for REE content by using method [34] and for dodecyl sulphate ion content by potentiometer method [31].

Page 5 (after Table 3).

values of -832.62±3.77 kJ/mol and -836.29 kJ/mol, specified in the databases [35-38].

Concerning 35, 36 - Thermodynamic Data base (RUSSIA). 37 - Data base for H,S, Cp data - Finnish Database: 

35. Thermal constants of substances. Handbook. Ed. V.P. Glushko/M.: USSR Academy of Sciences. Vol. 1978. 358 p.

36. Lidin R.A., Andreeva A.A., Molochko A.V. // Handbook. Constants of inorganic substances. Ed. "Dvora", M. 2006.

37. HSC Chemistry OutoKumpu Research OY (ver. 4.1.), Pori, Finland.

Author Response File: Author Response.pdf

Reviewer 3 Report

The author demonstrates a comprehensive discussion on procedures and observation occurs during ion flotation in recovering ytterbium. There are numbers of paper reported similar studies on this method, hence, the author has to emphasize on the significance of this study. Using sodium dodecyl sulphate as collector and different pH, the study is not really bringing new impact for readers.

  1. The common short form for sodium dodecyl sulphate is SDS, instead of NaDS. It is advisable to revise it.
  2. Lines 33: Please include the full chemical names of La and Ce here.
  3. Conclusion: It is rare to write the conclusions in point forms. Please revise it to a paragraph by relating all points and emphasize the significance of the paper.

Author Response

I agree with the reviewer there are many works concerning sodium dodecyl sulphate as collector and different pH, but there are much fewer works where issues are considered. and related to which forms of REE are extracted, and how best to achieve the extraction of valuable components.

Yes, there is a lot of literature on this method, but in my research I focus not only on the possibility of extracting REE cations, but also conduct thermodynamic calculations, since it is of great interest in what form and at what pH REE cations can be extracted - there are few such works.

Answers to the points:
Answers by points:
1. I agree - fixed on SDS, although I have met in the literature in a different way
2. I wrote the full names - of course, there was no need to shorten them.
3. Thanks for the comment - I tried to do as you advised.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

The content is still insufficient to be published as a full article. 

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