Assessment of a Novel Photocatalytic TiO₂-Zirconia Ultrafiltration Membrane and Combination with Solar Photo-Fenton Tertiary Treatment of Urban Wastewater

Round 1

Reviewer 1 Report

This manuscript by Deemter et al. aims to assess the combination of a new membrane with photo-Fenton process to remove some CECs from wastewater.

From my pont of view the experiments have been diligently conducted, and the manuscript is correctly written and formatted. It can be accepter as submitted, even if i advise the authors to use widely employ abreviation (CBZ and DCF instead of CAR and DIC)

Author Response

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Reviewer 2 Report

The main work of this paper is to assess combination of a photocatalytic TiO2-coated ZrO2 UF membrane with solar photo-Fenton at circumneutral pH for filtration and treatment of urban wastewater treatment plant (UWWTP) effluents. However, there are many important problems in the article. First, this work has no obvious ideas and highlights from synthesis to probe performance characterization. Secondly, as a technology application and transfer, the paper lacks the data results of sewage treatment system, what standards have been achieved after treatment, and whether it can be discharged directly. Third, the internal mechanism of membrane self-cleaning ability is lacking in this paper. Therefore, this promising work requires further research and is not recommended in current version for publication.

Other comments:

1. How is the self-cleaning ability of membrane measured and characterized in this paper? What level has it reached? Is the self-cleaning ability strong or weak?
2. What is the effective life of the membrane in the paper under light and dark conditions, and what is the effective working time of the system?

Author Response

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Reviewer 3 Report

This manuscript evaluates the combination of photocatalytic TiO₂-coated ZrO₂ UF membranes with solar photo-Fenton at neutral pH for filtration and treatment of urban wastewater treatment plant (UWWTP) effluents. Photocatalytic self-cleaning properties were tested with a UWWTP effluent under irradiation in a solar simulator. The performance of the simulator was judged by analyzing residues of caffeine (CAF), imidacloprid (IMI), thiamethoxam (THI), carbamazepine (CAR), diclofenac (DIC) and P. aeruginosa during solar Fenton treatment of the membrane. However, there are still some problems in the manuscript, which can be accepted after major revise.

1. There should not be too many statements of scientific knowledge in the Introduction section. For example, "The membrane principle is based on a series of physicochemical properties ......" is not necessary. "In addition, biofouling is basically formed by a well-known class of microorganisms" This paragraph should be combined and described in a simplified manner with the first paragraph of the Introduction.
2. Sunlight alone can activate H₂O₂, the effect of which is not considered in the manuscript.
3. The mechanism of self-cleaning of TiO₂-Zirconia ultrafiltration membranes should be clearly explained.
4. In Figures 7 and 8, why does bicarbonate promote the degradation of pollutants?
5. Figures 5, 6, 7 and 8 in the manuscript all require the addition of error bars.
6. The recent related references of Catalysts 2021, 11(10), 1206; Catalysts 2021, 11(5), 557; Environmental Science and Ecotechnology, 2022, 10, 100165; Chinese Chemical Letters 33 (2022) 1321–1324

Author Response

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Reviewer 4 Report

The article has novel, meaningful conclusions,The manuscript by Dennis Deemter and his colleagues, titled “Assessment of a novel photocatalytic TiO2-Zirconia ultrafiltration membrane and combination with solar photo-Fenton tertiary treatment of urban wastewater ”,is suitable for publication after minor modification of English.

The objective of this study was to assess combination of a photocatalytic TiO2-coated ZrO2 UF membrane developed in a previous study , with solar photo-Fenton at circumneutral pH for filtration of UWWTP effluents. Therefore, batches of UWWTP effluents were ultra-filtered by photocatalytic membranes and then treated by solar photoFenton. The results claimed by the authors are correct.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

I think the revised manuscript is suitable for the Journal.

Reviewer 3 Report

The revision is can be published as it is.