Fast Degradation of Tetracycline and Ciprofloxacin in Municipal Water under Hydrodynamic Cavitation/Plasma with CeO₂ Nanocatalyst

Round 1

Reviewer 1 Report

The manuscript deals with a very important problem, which is the degradation of antibiotics, which are important pollutants in water. Therefore, the manuscript deals with a topic of global interest and highly publishable. Before being published, authors must make the following changes.

1.    Keywords. Do not just repeat the title. I suggest rearrange.

2. Abstract. I believe that percentages of degradation should appear in the abstract, to support the results.

3.   Materials and Methods. I think the lines 110-124 are not necessary. They should be removed.

4. Materials and Methods. CeO2 preparation. The lines 136-171 should be explained better and in detail, to understand how the preparation of CeO2 was.

5.  Results. From page 5 to page 12, I recommend placing some bibliographic references that explain or contribute to results and conclusions of this study.

Author Response

Dear Editor,

We thank the reviewers for their attention to the manuscript. We took into account all the remarks and tried to address all of them. We send you our manuscript with the corrections made according to referees’ comments (they are marked yellow). Below, we give the list of our comments and corrections.

Answers to Referee #1:

Issue 1. Keywords. Do not just repeat the title. I suggest rearrange.

  The list of keywords was extended to better reflect the contents of the paper.

Issue 2. Abstract. I believe that percentages of degradation should appear in the abstract, to support the results.

The corresponding numerical value was added in the abstract.

Issue 3. Materials and Methods. I think the lines 110-124 are not necessary. They should be removed.

These lines were removed.

Issue 4. Materials and Methods. CeO₂ preparation. The lines 136-171 should be explained better and in detail, to understand how the preparation of CeO2 was.

A more detailed description of the synthetic procedure was provided. Including the reference of the original paper in which the synthetic procedure for the ceria sol was first reported

Issue 5. Results. From page 5 to page 12, I recommend placing some bibliographic references that explain or contribute to results and conclusions of this study.

In the Discussion section, we added more relevant references.

Reviewer 2 Report

In this manuscript, a CeO₂-nanoparticle-containing sonoplasma-treated system was developed to degrade tetracycline and ciprofloxacin in municipal water. The content of this paper is complete, but the following points need to be addressed before acceptance.

1. The Introduction of this manuscript should be shortened.

2. Please recheck the first three paragraphs of “2. Materials and Methods”.

3. The results and discussion section should be organized in a logical order. The characterization of CeO₂ nanoparticles should be at the beginning of this section.

4. There is no error bars in these figures. Please added the error bars.

5. The citation of figure was wrong in 3.6 Possible modifications to technological setup.

6. There are lots of grammar mistakes in this manuscript. Such as CeO2, 100 μl, 1.5-3.5 w/cm2, NH4+, NO3-, H2O, CO2. Please recheck and correct these mistakes.

7. Extensive English editing is needed.

Author Response

Dear Editor,

We thank the reviewers for their attention to the manuscript. We have taken all comments into account and all the amendments have been carefully revised. We are sending you our manuscript with the corrections we made highlighted in yellow. Below you will find our answers.

Answers to Referee #2:

Issue 1. The Introduction of this manuscript should be shortened.

The Introduction was shortened accordingly, though maintaining the comprehensive background of the work and the aims of the study.

Issue 2. Please recheck the first three paragraphs of “2. Materials and Methods”.

These lines were removed.

Issue 3. The results and discussion section should be organized in a logical order. The characterization of CeO₂ nanoparticles should be at the beginning of this section.

As a matter of fact, all the authors have had an extensive discussion about the logic of the presentation. In the final version of the manuscript, the characterization of CeO2 nanoparticles was placed directly before the discussion of catalyst effect, because the preparation of the nanoparticles is not the focus of the paper and they are not brought up until the section on catalysis. If this characterization section is in the beginning of the discussion, it would confuse the reader and shift the focus of the research. We prefer not to change the structure of the Discussion section.

Issue 4. There is no error bars in these figures. Please added the error bars.

In Figs. 3 and 4, we added error bars.

Issue 5. The citation of figure was wrong in 3.6 Possible modifications to technological setup.

The citation was corrected.

Issue 6. There are lots of grammar mistakes in this manuscript. Such as CeO2, 100 μl, 1.5-3.5 w/cm2, NH4+, NO3-, H2O, CO2. Please recheck and correct these mistakes.

We apologize for some carelessness in our manuscript. We did our best to fix all the mistakes.

7. Extensive English editing is needed.

The English quality was improved by a native speaker.