Performance Evaluation of a Romanian Zeolite: A Sustainable Material for Removing Ammonium Ions from Water
, Daniela Cristina Berger 1, Nicolaie Cicerone Marinescu 2 and Mircea Stefan 3,*Round 1
Reviewer 1 Report
Comments and Suggestions for Authors The work is original and well written. Some issues must be reviewed. 1- It was not possible to observe lamellar strictures in the SEM images. 2- Based on which measurements the authors state that the lamellae are 100nm thick. 3- Authors must indicate the region in which the pore size was measured in the SEM images. 4- Were desorption tests carried out? I suggest that the authors carry out desorption tests. 5- To identify the presence of functional groups on the surface of the adsorbent, I suggest doing an FTIR. 6- The authors must show the BET adsorption isotherm and discuss the results further. Comments on the Quality of English LanguageI suggest reviewing the language in English
Author Response
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Reviewer 2 Report
Comments and Suggestions for AuthorsThis study thoroughly assesses the effectiveness of Romanian Zeolite in eliminating ammonium ions from water, yielding a wealth of experimental data. However, the manuscript suffers from a lack of coherent organization and contains several editing errors. In summary, I believe substantial revisions are necessary for this article to meet the standards for publication in the journal "Sustainability."
1. The article contains an overwhelming number of figures. To enhance the ease of comparison among the different materials, it would be beneficial to merge Figures 5 through 8 into a single figure for each category, similar to Figures 9 and 10. This adjustment would help reduce the total figure count to fewer than 8. Additionally, it is important to ensure that the formats of Figures 4(a-d), 5-8, and 9-10 are consistent. The author should also meticulously review the font sizes of both the horizontal and vertical axes, as well as the image resolution, etc.
2. The XRD patterns should be annotated with the appropriate crystal facet indices corresponding to each phase.
3. To ensure the precision of the experimental data, it is suggested to incorporate parallel data (error bars).
4. To investigate the potential use of this material for ammonium removal, it is essential to carry out experiments on ion competition, assess cycling stability, and evaluate ammonium extraction from actual wastewater sources.
5. Some literatures related to photocatalytic or photoelectrocatalytic removal of NH4+ and other pollutants are recommended to cite, such as Environ Res, 205 (2022), 112434; Environ Res, 249 (2024), 118497. These references will provide further support for the discussion in the background introduction.
Comments on the Quality of English Language
Minor editing of English language required.
Author Response
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Reviewer 3 Report
Comments and Suggestions for AuthorsI have reviewed the manuscript and find it of interest however the following concerns have to be addressed.
In the Abstract
1- Lines 40-41 needs to be rephrased concerning the ionic strength, please indicate only the effect of ionic strength.
In Materials and Methods
1- Under table 1 and table 2, please correct the caption.
In Results and discussion
1- In line 200, please change "in their experiments", in line 207 and 208, capital letters in the middle should be changed into small letters.
2- Please rephrase lines 227-228.
3- In table 3, Quantity % is written above the structure!
4- In table 4, what do you mean by "K" beside each element?
5- In line 238, please correct the pH of zero potential.
6- In line 240, please rephrase, don't start with "As you know".
7- Please rephrase lines 254-257, they are not clear.
8- please correct symbols in lines 264 and 268.
9- In line 288, "the results presented in table 4", it is not table 4 but 5.
10- Although Langmuir model is the one with the highest R2 values but the value of some parameters in other isotherms are indicative and it offers a better and comprehensive understanding of the steps of the adsorption mechanism ( as example the values of the bT of Temkin), so please make use of them to offer a complete prediction of the steps of the mechanism, to assist you on that I refer you to the following recent article https://doi.org/10.1007/s13399-022-02709-5
11- Please rephrase lines 314-316, they are confusing and please correct CAG to GAC across the manuscript.
12- In lines 322-323, please note that the increase in the adsorption with increasing the pH, is due to increasing the negative charges on the adsorbent surface resulting from the deprotonation process.
13- In the paragraph starting at line 334, please don't compare with the initial adsorption capacity, but state the effect of increasing the pH and IS on the adsorption process, increasing or decreasing.
In conclusions
1- The increase in adsorption with increasing temperature indicates that the adsorption process is endothermic.
References
1- Please unify the way references are written, the year either bold or not and at the end or front, please check references 11, 16,20,22, 26, 27, 37and correct 31.
2- Please add some recent references (2022-2024).
Comments on the Quality of English LanguageEnglish editing is required!
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsThe XRD patterns need to be labeled with the corresponding crystal facets, and it is advisable to include error bars in at least Figure 9.
Author Response
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Reviewer 3 Report
Comments and Suggestions for AuthorsI have reviewed the revised version, the following needs to be attended to:-
1- Some minor English editing is still required, as example lines 37-38 in the abstract.
2- If you are not welling to consider point no. 9, results and discussion section, in my previous report, then at least indicate that "the mechanism starts with electrostatic attraction between positively charged ammonium ion and negatively charged active sites followed by formation of adsorbed mono-layer" and reference the given article ( https://doi.org/10.1007/s13399-022-02709-5) because that is what your experimental results are showing.
Comments on the Quality of English LanguageMinor English editing is still required.
Author Response
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