Magnetic Metal–Organic Framework Enhanced Inorganic Coagulation for Water Purification
Round 1
Reviewer 1 Report
In this paper, two flocculant materials were synthesized and used for the treatment of organic and algal pollutants in water, with several questions as follows
1. Is there any Fe, Zn etc. ions dissolved in the solution after treatment?
2, it was said in the paper in line 58-60 “However, magnetic seeds are significantly affected by the external environment, and 58 it is crucial to make a magnetic seed to make it stable in an acidic solution environment 59 and avoid the destruction of the strongly acidic flocculant solution environment.”,
then are the magnetic ions used in this paper structurally destroyed under acidic conditions such as pH 1-3?
3.the removal efficiency of DOC is about 70%, what is not removed? Why can't it be removed?
no comments about the quality of English Language.
Author Response
Dear Editor,
We respond the reviewers' comments and revise the manuscript. Our response (R) to reviewer’s questions (Q) is follows point by point:
Q1: Is there any Fe, Zn etc. ions dissolved in the solution after treatment?
R1: Thank you for your comments. We have tested the ions in the solution in the experiment and found that they are in line with our national standards. Therefore, the content of Fe ions is very small.
Q2: it was said in the paper in line 58-60 “However, magnetic seeds are significantly affected by the external environment, and 58 it is crucial to make a magnetic seed to make it stable in an acidic solution environment 59 and avoid the destruction of the strongly acidic flocculant solution environment.”,
then are the magnetic ions used in this paper structurally destroyed under acidic conditions such as pH 1-3?
R2: Thank you for your careful review and suggestions. Normally, the effective pH of flocculation is 5-8. When the pH is 1-3, we generally do not discuss. Because an extremely acidic environment destroys flocculation.
Q3: the removal efficiency of DOC is about 70%, what is not removed? Why can't it be removed?
R3: Thank you for your advice. In the process of flocculation, most of the DOC that can be removed is large molecules, and the DOC that cannot be removed by flocculation may be small molecules.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Manuscript (water-2582338)
1- The introduction needs more studies to highlight the novelty of this work. Cite some studies from the host journal.
2- SEM images are not clear enough to give more information about the diameter range, shape of materials used, etc., so TEM is recommended for this purpose.
3- Figure 4. need to add all information (marking) on the Figure to better understand the shifting in peaks and make it more readable.
4- Same thing about Figure 5. (No. 3)
5- Line 295 As shown in Figures 6d and 5e ?? correct it.
6- The experimental mechanisms should be added to the manuscript.
7- 3.4 Iron species analysis paragraph is too difficult and needs to be modified and even rewritten.
Author Response
Thank you for your thoughtful suggestions. We have revised the manuscript according to the requirements. Please refer to Word for specific responses.
Author Response File: Author Response.pdf
Reviewer 3 Report
The manuscript gave a good result and a detailed analysis, showing magnetic seed role (magnetic metal organic framework) of enhancing coagulation. It fits the topic of the journal. Meanwhile, MOF materials and derivatives have been used for water-related application, including water purification and water splitting. Some recent works should be cited, such as “Stringing Bimetallic Metal-Organic Framework‐Derived Cobalt Phosphide Composite for High‐Efficiency Overall Water Splitting”, “CoMo carbide/nitride from bimetallic MOF precursors for enhanced OER performance”, etc.
Please address the following concerns as follows.
1. Please carefully check language, format and grammar, ensuring free errors before publication.
2. Abbreviation of those analytical technologies’ full name such as scanning electron microscope and X-ray diffractmeter, has been defined at the first of appearance. Do not repeat again at “2.4. Analytical methods”.
3. Modify the title of “3.8. Application in algae water” as follows: “3.8. Application in algae water treatment”.
4. Modify the title of “slow mixing time effect” of X-axis in Figure 8 as follows “slowly mixing time effect”.
5. If possible, please add effect of coagulation for algae at varying concentration.
Please carefully check language, format and grammar, ensuring free errors before publication.
Author Response
Thank you for your thoughtful suggestions. We have revised the manuscript according to the requirements. Please refer to Word for specific responses.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
The authors have satisfactorily addressed all comments made on the original submission. The revised version of the manuscript is recommended for publication.
Another thing: It would be more interesting if the authors added a full description of the process, which means the coagulation and flocculation process mechanisms.
