Towards Sustainable Viscose-to-Viscose Production: Strategies for Recycling of Viscose Fibres

1.    Authors should focus their rather general statements for reprocessing discarded pre-consumer wastes (e.g. line 81, 393, 403) to the real finding, which is the reprocessing of clean viscose fibres into viscose fibres.

Answer:  Thank you for highlighting this. We have revised the manuscript according to the reviewer’s comment.

2.    As a consequence authors should address in their discussion at least a current limitation of the study: fibre blends, dyed material (e.g. crosslinking through bifunctional reactive dyes, finishing), post-consumer wastes

Answer:  Thank you for highlighting this. We have updated the results where we address the limitations in this study, line 288.

3.    The overall impression is more towards a technical report and it would be interesting, how the concentrations of alkali 19%, 25% 36 %, the duration of the second steeping were chosen.

Answer: Thank you for highlighting this. We have updated the text and added information that explains the rationale behind the choice of alkali concentration, line 131.

4.    It would have been interesting for comparison, how properties of a spin dope from single steeping with final concentration 12% NaOH would have been.

Answer: Thank you for the comment. We did not perform single steeping with 12% alkali concentration since this would not have allowed the cellulose to transform into alkali cellulose, which we indirectly comment on in the manuscript (p.3, lines 123-124, please also see references 6 and 35).

5.    In Figure 4 or discussion: What is the theoretical gamma number calculated on the amount of CS2 used for the different experiments?

Answer:  The theoretical gamma number may be calculated, although not of relevance since the degree of substitution, and thus gamma number, which is much more dependent on the reactivity of the cellulose and not on the CS2 charge, as has been established in previous studies, for example: Östberg, L., Håkansson, H., & Germgård, U. (2012). Pulp reactivity for viscose. In BioResources (Vol. 7, Issue 1).

6.    Conclusions 397: It is clear and not really new that we can skip the ageing step after steeping, as the molecular weight of the viscose fibres does not require reduction for the process. Pls. reformulate

Answer: Thank you for the comment. We have rephrased the sentence in the conclusions.

line 279 pls check sentence

Answer: Thank you for highlighting this. The sentence has been updated (p.8, line 279).

1. In paragraph 2.1, please provide information about the type of distilled water used. Standardized testing methods are used throughout the work, so it would be good to provide information on the class of water prepared using the Milli-Q device, in accordance with the ISO 3696 standard.

Answer: Thank you for the comment. We have added additional information about the water used. (line 99)

2. In paragraph 2.3, please detail the methodology for obtaining fibers. Please provide the value of the stretch in the coagulation bath and the temperature at which this process was carried out. If I understand correctly, the stretching process was carried out in air, at room temperature. Please provide detailed parameters for the fiber stretching process.

Answer: Thank you for the comment. Yes, the stretching was performed in air. We have added additional information about the fibre stretching process. (lines 139-142)

1-title need to change to be more attractive to reader.

Answer: Thank you for the comment. We considered several titles during the writing process and concluded that the chosen title best described our work.

2-abstract need to rewrite again.

Answer: Thank you for the comment. We have revisited the abstract. If there are any specific parts or details that you want us rewrite, we would be much obliged if you could specify them.

3-in key words you indict to MMCF and the abstract not contain any thing about it.

Answer: Thank you for the comment. MMCF is mentioned in the Introduction for the first time on line 55. Moreover, we highlight that viscose is one type (and the most common type) of MMCF. Since the focus of our study has been viscose, this is the wording used in the abstract. However, in general terms we are highlighting the potential of recycling MMCF, and this is why we added MMCF as a key word.

4-at page 3 line 134 where figure S1????

Answer: Thank you for the comment. On page 3, line 134 we are not referring to Figure S1 but to Figure 1, which is displayed below the text on page 4.

5-page 6 line 271 where figure S1??

Answer: Thank you for the comment. Figure S1 is located on page 1 in the document Supplementary Information.

6-at page 10 line 376 where figure S3??/

Answer: Thank you for the comment. Figure S3 is located on page 2 in the document Supplementary Information.

7- in methodology please clear the difference between S.S and D.S the point not clear enough.

Answer: Thank you for the comment. We have updated the text on page 3, line 122., to make it clear that S.S denotes one steeping step and D.S that the steeping step is performed twice.

8-support your work with chemical equation to explain how cellulose xanthate formed, please put this chemical equation necessary.

Answer: Thank you for the comment. We have added a reference that displays the reaction scheme on how cellulose xanthate is formed.

9-conclusions need to be rewrite again.

Answer: Thank you for the comment. We have revised the conclusions.

10-all references need to check again where most of them not contain page and volume number.

Answer: Thank you for the comment. We have updated the references, so they all contain page and volume number.

please rewrite this manuscript again and take care from some expressing for example in conclusions at line 394 you write (the need) and at figure 3 capture you write via single steeping and using 36% CS2 remove "and" please.

Answer: Thank you for the comment.  We have updated the caption to figure 3. We have read through the manuscript again to assure that the manuscript is well-written.