Biochar from Lemon Stalks: A Highly Active and Selective Carbocatalyst for the Oxidation of Sulfamethoxazole with Persulfate
, Ioannis D. Manariotis 4, Danae Venieri 5, Stavros G. Poulopoulos 6 and Dionissios Mantzavinos 1Round 1
Reviewer 1 Report
Manuscript: Biochar from lemon stalks: a highly active and selective carbo-catalyst for the oxidation of sulfamethoxazole with persulfate
Number: catalysts-2155343
The author prepared biochar derived from lemon stalks, and the biochar is used to activate persulfate ions for oxidizing sulfamethoxazole. The study confirm hydroxyl radical was dominant contribution on the oxidization of sulfamethoxazole. This content is interesting and it meets the scope and standard of your journal or special issue. I recommend publishing this paper after minor revision.
1. The operating conditions for XRD test is unclear, suggesting supplement information.
2. Why the author studied the effect of water matrix, please explain.
3. The electrochemical analysis is weak, I suggest the author to reference this ref (Bioresource technology 296, 122319) for enhancing analysis and discussion.
4. The author should clarify that why use methanol and t-butanol as scavengers?
5. The study about scavenger is good, but the discussion is too weak. I suggest the author enhancing discussion and analysis and some references for you (Chemical Engineering Journal 431, 133339; Water Research 207, 117849).
6. In conclusions, the author should give some summary and future perspective.
Author Response
Reviewer 1
Manuscript: Biochar from lemon stalks: a highly active and selective carbo-catalyst for the oxidation of sulfamethoxazole with persulfate
Number: catalysts-2155343
The author prepared biochar derived from lemon stalks, and the biochar is used to activate persulfate ions for oxidizing sulfamethoxazole. The study confirm hydroxyl radical was dominant contribution on the oxidization of sulfamethoxazole. This content is interesting and it meets the scope and standard of your journal or special issue. I recommend publishing this paper after minor revision.
We would like to thank the reviewee for his/her valuable comments. The comments help us to improve the quality of the manuscript
- The operating conditions for XRD test is unclear, suggesting supplement information.
They are the default conditions for voltage and scan rate
- Why the author studied the effect of water matrix, please explain.
The different water matrices were studied for two reasons: (a) to determine the activity of the biochar in different and more complex matrices; evaluating how the increase of the different ions and organic matter can influence the degradation process and (b) to explore the possibility of the antibiotic oxidation in waste water matrices as a real water source.
- The electrochemical analysis is weak, I suggest the author to reference this ref (Bioresource technology 296, 122319) for enhancing analysis and discussion.
The reference was added
- The author should clarify that why use methanol and t-butanol as scavengers?
Methanol and t- butanol are radical scavengers. Both alcohols act as radical scavengers; methanol reacts with both sulfate and hydroxyl radicals at comparable rates, while t–butanol reacts preferentially with hydroxyl radicals
- The study about scavenger is good, but the discussion is too weak. I suggest the author enhancing discussion and analysis and some references for you (Chemical Engineering Journal 431, 133339; Water Research 207, 117849).
The references were added
- In conclusions, the author should give some summary and future perspective.
Action taken: Done, the conclusion paragraph was revised.
Reviewer 2 Report
1. The introduction should be revised, the newest persulfate activation developments should be added, which could be supported by the following papers: Chemical Engineering Journal 438 (2022) 135656, Separation and Purification Technology 289 (2022) 120806, Separation and Purification Technology 295 (2022) 121293.
2. The descriptions of Figure 1 for the sample was ambiguity, especially for the crystallite structure and rich Ca element, please revise this part.
3. Figure 2, there lacked the specific symbol for different peak in figure, please add.
4. Figure 3, similar to Fig. 2, there need the specific symbol for the potential functional groups in figure.
5. The quality for all figures of characterizations should be improved.
6. Section 2.3.2, what was the concentration for the scavengers?
7. The selective feature should be highlighted in the result and discussion.
Author Response
We would like to thank the reviewee for his/her valuable comments. The comments help us to improve the quality of the manuscript
- The introduction should be revised, the newest persulfate activation developments should be added, which could be supported by the following papers: Chemical Engineering Journal 438 (2022) 135656, Separation and Purification Technology 289 (2022) 120806, Separation and Purification Technology 295 (2022) 121293.
Action taken: The references were added in the revised text
- The descriptions of Figure 1 for the sample was ambiguity, especially for the crystallite structure and rich Ca element, please revise this part.
Action taken: Done
- Figure 2, there lacked the specific symbol for different peak in figure, please add.
Action taken: Done, it was revised
- Figure 3, similar to Fig. 2, there need the specific symbol for the potential functional groups in figure.
Action taken: Done, it was revised
- The quality for all figures of characterizations should be improved.
Action taken: Done, it was revised
- Section 2.3.2, what was the concentration for the scavengers?
The concentration was 10 g/L for the alcohols and 100 mg/L for NaN3.
Action taken: The information was added in the revised text
- The selective feature should be highlighted in the result and discussion.
Action taken: The following phrase was added in the revised text “Depending …different antibiotics.”
