Degradation of Organics and Change Concentration in Per-Fluorinated Compounds (PFCs) during Ozonation and UV/H2O2 Advanced Treatment of Tertiary-Treated Sewage
, Jai-yeop Lee 1,2, Hyun-Ju Ha 3, In Geol Yi 3, Da-Hye Hong 3, Chang-Min Park 3, Mok-Young Lee 3 and Ilho Kim 1,2,*
Round 1
Reviewer 1 Report
- English should be revised.
- The abstract should be more informative and contains the core findings for each case studied in this work. Please revise it.
- The dimensions of the reactor listed in item 2.1 do not match the calculated volume of 17.5 L. Please recheck it.
- Why did you choose stainless steel as the material of the reactor?
- What is the rule for choosing the reaction time of 20 min for the part of this study? Then 40 min and 50mg/ L H2O2? Please explain.
- Since you prepared the polluted solution (Line: 108), why did you propose that you have treated real wastewater (Line: 81 and Line:182)?
- A schematic of the present reactor should be added.
- The captions (a, b, and c) should be added to the graphs in Fig. 1.
- It is preferred to add graphs containing removal efficiency rather than pollutant degradation.
- In Line 163, correct Fig. 3 to Fig. 2.
- In Line 220, correct Fig. 3 to Fig. 4.
- Line 225, where is Fig. 1.2?
- The addition of a summary table containing the core results of all parts is very important to the readers.
- Recent references should be cited because more of the references cited in this work is old.
Author Response
Response to Reviewer 1
Thank you very much for your comments that helped us improve this manuscript.
- English should be revised.
Response: English has been revised throughout the manuscript.
- The abstract should be more informative and contains the core findings for each case studied in this work. Please revise it.
Response: Revised accordingly.
- The dimensions of the reactor listed in item 2.1 do not match the calculated volume of 17.5 L. Please recheck it.
Response: Checked and corrected accordingly.
- Why did you choose stainless steel as the material of the reactor?
Response: Stainless steel is easy to manufacture in a reaction tank, like cylinder shape, prevents UV exposure, and is corrosion resistant in a chlorine-free water treatment process.
- What is the rule for choosing the reaction time of 20 min for the part of this study? Then 40 min and 50mg/ L H2O2? Please explain.
Response: The reaction time has been chosen according to the experimental results, also 50mg/ L H2O2 shows the highest degradation efficiency. We show the most efficient time and degradation values among many experiments.
- Since you prepared the polluted solution (Line: 108), why did you propose that you have treated real wastewater (Line: 81 and Line:182)?
Response: That sentence has been corrected, Due to the very low concentration of PFCs in actual sewage water, the solution was only prepared for the spike of PFCs concentration.
- A schematic of the present reactor should be added.
Response: A schematic diagram for the UV reactor has been added.
- The captions (a, b, and c) should be added to the graphs in Fig. 1.
Response: The captions have been added.
- It is preferred to add graphs containing removal efficiency rather than pollutant degradation.
Response: A graph has been added to show the removal efficiency.
- In Line 163, correct Fig. 3 to Fig. 2.
Response: Corrected accordingly.
- In Line 220, correct Fig. 3 to Fig. 4.
Response: Corrected accordingly.
- Line 225, where is Fig. 1.2?
Response: Corrected accordingly.
- The addition of a summary table containing the core results of all parts is very important to the readers.
Response: It’s important to understand the results but it’s difficult to add in one summary table.
- Recent references should be cited because more of the references cited in this work is old.
Response: Revised accordingly.
Reviewer 2 Report
The paper is concerned with investigating the effect of H2O2 addition, ozone feed rate and UV addition on the change of concentration of organics such as CODMn, CODCr, TOC and PFCs in tertiary treated sewage of STP during O3 and UV/ H2O2 process. The O3/UV/H2O2 process was an effective method for treating refractory organics. However, AOPs are not sufficient to fully treat the PFCs compound, and thus, additional 26 procedures are required to degrade PFCs. The paper covers some important issues but some points should be corrected. I recommend the manuscript for publication in this Journal after major revision.
Some comments are listed below:
- Page 1, Line 18-13, please check the grammar
- Page 1, Line 27-28, please check the grammar and rewrite
- Page 1, lines 51-54, please cite the following paper,
Improving peroxymonosulfate activation by copper ion-saturated adsorbent-based single atom catalysts for the degradation of organic contaminants: electron-transfer mechanism and the key role of Cu single atoms
- In the section of Introduction, the authors should more underline the novelty of research.
- Page 3, line 111-113, “The perfluorinated compound test method was carried out using ES 04506.1 (perfluorinated compound-liquid chromatography-tandem mass spectrometry) announced in the Water Pollution Process Test Standards” please give the reference
- Please rearrange the layout of the table 1 properly
- Figure 1 is confusing, please mention as Fig. 1a, 1b and 1c and discuss accordingly.
- Please, you should mention all figures 1,2,3,4,5 divide accordingly to the a,b,c,d
- Please revised and discussed clearly section 3.6 Effect of O3 and O3/UV on the TOC and PFCs concentration.
- Please note the upper case and lower case in the entire manuscript.
- The English language of the paper should be improved.
- Discussion must be improved.
Comments for author File: 
Comments.pdf
Author Response
Response to Reviewer 2
Thank you very much for your kind review. We have made revisions accordingly.
Some comments are listed below:
1. Page 1, Line 18-13, please check the grammar
Response: Grammar has been checked and corrected.
2. Page 1, Line 27-28, please check the grammar and rewrite
Response: Grammar has been checked and corrected.
3. Page 1, lines 51-54, please cite the following paper,
Response: Revised and corrected accordingly.
Improving peroxymonosulfate activation by copper ion-saturated adsorbent-based single atom catalysts for the degradation of organic contaminants: electron-transfer mechanism and the key role of Cu single atoms
1. In the section of Introduction, the authors should more underline the novelty of research.
Response: Revised accordingly.
2. Page 3, line 111-113, “The perfluorinated compound test method was carried out using ES 04506.1 (perfluorinated compound-liquid chromatography-tandem mass spectrometry) announced in the Water Pollution Process Test Standards” please give the reference
Response: Reference has been added.
3. Please rearrange the layout of the table 1 properly
Response: Corrected accordingly.
4. Figure 1 is confusing, please mention as Fig. 1a, 1b and 1c and discuss accordingly.
Response: Revised accordingly.
5. Please, you should mention all figures 1,2,3,4,5 and divide accordingly to the a,b,c, and d.
Response: Revised accordingly.
6. Please revised and discussed clearly section 3.6 Effect of O3 and O3/UV on the TOC and PFCs concentration.
Response: Revised accordingly.
7. Please note the upper case and lower case in the entire manuscript.
Response: Corrected accordingly.
8. The English language of the paper should be improved.
Response: English has been revised throughout the manuscript.
9. Discussion must be improved.
Response: Revised accordingly.
Reviewer 3 Report
This paper deals with the degradation of organic pollutants and change of PFCs concentration during advanced oxidation processes of tertiary treated sewage. The experiments are good and the paper provided advancement in scientific knowledge, although the article could be improved along the following guidelines:
* Introduction: authors must use other recent references: Journal of Environmental Management 304 (2022) 114236; Process Safety and Environmental Protection 136 (2020) 49-55; Chemical Engineering Journal 411 (2021) 128392; Journal of Saudi Chemical Society 25 (2021) 101326; Environmental Pollution 291 (2021) 118014; Water 14(2022) 750
* Page 4 : L129-137 : add more details for the determination of CODcr and CODMn
* Page 5:L163-180: Figure 3 must be figure 2
* Page 6: L207: Fig.4 à Fig. 3
* Page 7: L220: Figure 3 à Figure 4
* Page 7: L231: CODmn à CODMn
Author Response
Response to Reviewer 3
Thank you very much for your valuable comments that helped us improve this manuscript.
1. Abstract: The full names of the abbreviations should be provided when they appear firstly in the text
Response: Corrected accordingly.
2. Overall the quality of English and grammar needs to be thoroughly checked. The authors need to work with a native English-speaking editor to help correct the mistakes throughout the manuscript.
Response: English has been revised throughout the manuscript.
3. The logic in the introduction should be improved. The application of different AOPs and their combinations for the removal of organic pollutants should be discussed and compared. The authors need to connect the state of the art to their paper goals. Please follow the literature review with a clear and concise state of the art analysis. This should clearly show the knowledge gaps identified and link them to the paper goals. Key references:
Response: Revised accordingly
https://doi.org/10.1016/j.arabjc.2021.103366
https://doi.org/10.1016/j.chemosphere.2019.04.160
1. Rewrite the research hypothesis (last paragraph of the introduction section)
Response: Corrected accordingly.
2. The discussion section should be expanded to highlight the scientific contribution of this study to this field.
Response: Revised accordingly.
3. Error bars are missing in the figures.
Response: In the removal efficiency graph the error bars have been provided. But for the other figures, because of the clarity, we didn't put the error bars.
4. The conclusions are simple and inadequate. The authors should emphasize the contribution of work, future work, technology, or knowledge. Also, the shortcomings of this manuscript need to be discussed in the conclusion
Response: Revised accordingly.
Reviewer 4 Report
This manuscript (sustainability-1702736) investigates the degradation of organic pollutants and change in concentration of perfluorinated compounds in the wastewater treatment plants during advanced oxidation processes based on H2O2 addition, ozone and UV irradiation. The effect of experimental parameters such as hydrogen peroxide addition, pH and ozone feed rate, as well as UV irradiation on the treatment efficiency was studied. The topic of this manuscript is suitable for publication in this Journal and interesting results were presented.
To my opinion, after revision, I think the quality of this manuscript should be revised according to the following issues.
My comments:
- Abstract: The full names of the abbreviations should be provided when they appear firstly in the text
- Overall the quality of English and grammar needs to be thoroughly checked. The authors need to work with a native English-speaking editor to help correct the mistakes throughout the manuscript.
- The logic in the introduction should be improved. The application of different AOPs and their combinations for the removal of organic pollutants should be discussed and compared. The authors need to connect the state of the art to their paper goals. Please follow the literature review with a clear and concise state of the art analysis. This should clearly show the knowledge gaps identified and link them to the paper goals. Key references:
https://doi.org/10.1016/j.arabjc.2021.103366
https://doi.org/10.1016/j.chemosphere.2019.04.160
- Rewrite the research hypothesis (last paragraph of the introduction section)
- The discussion section should be expanded to highlight the scientific contribution of this study to this field.
- Error bars are missing in the figures.
- The conclusions are simple and inadequate. The authors should emphasize the contribution of work, future work, technology, or knowledge. Also, the shortcomings of this manuscript need to be discussed in the conclusion.
Author Response
Response to Reviewer 4
Thank you very much for the review. We have made revisions accordingly.
* Page 4 : L129-137 : add more details for the determination of CODcr and CODMn
Response: Revised accordingly.
* Page 5:L163-180: Figure 3 must be figure 2
Response: Corrected accordingly.
* Page 6: L207: Fig.4 à Fig. 3
Response: Corrected accordingly.
* Page 7: L220: Figure 3 à Figure 4
Response: Corrected accordingly.
* Page 7: L231: CODmn à CODMn
Response: Corrected accordingly.
Round 2
Reviewer 2 Report
Accept in present form
Reviewer 4 Report
All comments have been addressed properly, so the article suggested publishing with its present form. A further read throughout to correct minor spelling mistakes is worth doing.
