Iprodione Removal by UV-Light-, Zero-Valent Iron- and Zero-Valent Aluminium-Activated Persulfate Oxidation Processes in Pure Water and Simulated Tertiary Treated Urban Wastewater

Round 1

Reviewer 1 Report

The following are comments regarding Water manuscript 1156109, titled ‘Iprodione Removal by UV-light-, Zero-Valent Iron- and Zero-Valent Aluminium-Activated Persulfate Oxidation Processes in Pure Water and Simulated Tertiary Treated Urban Wastewater,’ by Bahareh Montazeri, Olga Koba Ucun, Idil Arslan-Alaton, and Tugba Olmez-Hanci. As the title states, the authors report on the removal of the fungicide iprodione using UV-light, zero-valent iron, zero-valent-aluminium, and persulfate oxidation in two matrices, distilled water and simulated tertiary treated urban wastewater.

My fundamental objection to this work is its environmental relevance and significance. The authors conducted these experiments using 2 and 10 mg/L of iprodione, which, as the authors acknowledge in section 2.2, Experimental Procedures, are much higher than environmentally relevant concentrations, as a matter of fact, by orders of magnitude. The authors justify these unrealistically high concentrations with a statement hinting at analytical difficulties at lower concentrations. In fact, these concentrations approach the solubility and therefore maximum concentration of this compound in aqueous solutions. In addition, distilled water, is also an unrealistic environmental matrix.

Author Response

Please find our answers to Reviewer 1 in the below attached file.

Author Response File: Author Response.docx

Reviewer 2 Report

I recommend to publish this article in Water journal after minor revision. The Figures are not readable - please improve the quality of them.  

Comments for author File: Comments.pdf

Author Response

Please find below our answers to Reviewer Nr. 2 attached as a word file.

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Reviewer 3 Report

This study evaluated the Degradation of iprodione (IPR) by UV-C light-, zero-valent iron- (ZVI) and zero-valent aluminum (ZVA)-Activated persulfate (PS) oxidation processes. This study contained novelty and several suggestions are provided for improvement. Thus, I suggested this study can be published after minor revision.

1. The original concentration of the target compound is too high for the actual situation, please highlight the necessity of setting concentration.
2. The Figures (Such as Figure 1) in this study are confused, and the color figures are suggested to improve the distinction.
3. The conclusion should be simplified, and the key conclusion should be provided.

Author Response

Please find below our answers to Reviewer Nr. 3 attached as a word file.

Author Response File: Author Response.docx

Reviewer 4 Report

This study presents the degradation of iprodione (IPR), a fungicide under UV-C light-, zero-valent iron- (ZVI) and zero-valent aluminium (ZVA)-11 activated persulfate (PS) oxidation processes. Experiments are conducted in a systematic manner. It also presents some interesting results that will be attractive to readers. However, authors need to address the following issues.

1. Introduction lacks the discussion on why UV-C activated PS is compared to the performance of ZVA and ZVI activation of PS.
2. Introduction, mention the reactions and equation for the UV-C activation of PS.
3. Page no.4, rewrite the sentence 159-160
4. In section 3.2, What are the side reactions that can occur during the activation of PS with zero valent metals at acidic condition? Is there any water splitting or hydrogen evolution reactions observed?
5. In section 3.1 and 3.5, why does the UV-C/PS based degradation studies alone are conducted in pH 6.2 solution whereas ZVI/ZVA based studies carried out at pH 3.0? In such case, how the removal efficiencies are comparable?
6. Is there any, photolysis of IPR observed under UV-C light?
7. In section 3.5, why does the ZVI/PS showed better performance compared to ZVA/PS while treating the real WW?
8. Overall, manuscript needs to be revised for language correction.

Comments for author File: Comments.pdf

Author Response

Please find below our answers to Reviewer Nr. 4 attached as a word file.

Author Response File: Author Response.docx

Round 2

Reviewer 4 Report

Authors addressed most of the comments satisfactorily. However, authors need to address the following comment.

In the revised manuscript, Eq (1) need to be checked for the correctness. Sulfate radicals are wrongly displaced by sulfate ions according to the theoretical explanation given by the authors.