Preparation and regeneration of iron-modified nanofibres for low-concentration phosphorus-containing wastewater treatment

In this study, nanocellulose (CNFs) was prepared by a mechanical shearing method, a simple and pollution-free process. Iron hydroxide was loaded on nanocellulose, a natural macromolecule derived from bamboo, to produce the second-generation iron-loaded nanocellulose for the removal of low-concentration phosphorus from wastewater. We found that the best modified ferric salt was ferric chloride. When the mass ratio of Fe(OH)3 and CNFs was 1.5 : 1, freeze-drying with liquid nitrogen yielded the best adsorption performance. The adsorption process of Fe(OH)3@CNFs followed the pseudo-second-order kinetics and belonged to chemical adsorption. Regeneration experiments showed that after 10 cycles of adsorption–regenerations of the adsorbent, the phosphorus adsorption efficiency was still stable at 80% of the initial material. The prepared adsorbent was characterized by the BET surface area measurement, scanning electron microscopy and FT-IR. The surface morphology, pore size and elements of materials before and after iron loading were analysed. Compared with other adsorbents, the phosphorus removal performances of the second-generation iron-loaded nanocellulose were superior. Compared with the first-generation material, the second-generation adsorbent is simpler and more environmentally friendly.

The Conclusion section is too short, it should be written properly. And also mention like can be reused many times, it is better to mention how many times can be used. English and grammatical errors should be rectified during the revision of the paper.

Recommendation?
Accept with minor revision (please list in comments)

Comments to the Author(s)
How to improve the economy and recycling degree of low concentration phosphorus wastewater treatment is one of the difficulties of municipal domestic wastewater treatment. This paper described the adsorption of low concentration phosphorus from simulated waste water source using bamboo-based nanocellulose fiber loaded with iron hydroxide (Fe(OH)3@CNFs). As an environmentally friendly adsorbent material, it has great potential for application. On the other hand, it can provide technical support for China's continuous improvement of sewage discharge standards, and it can also provide a feasible way for the recovery and utilization of phosphorus resources.  Title: Preparation and regeneration of iron-modified nanofibres for low concentration phosphorus-containing wastewater treatment Manuscript ID: RSOS-190764 Thank you for your submission to Royal Society Open Science. The chemistry content of Royal Society Open Science is published in collaboration with the Royal Society of Chemistry.
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RSC Subject Editor:
Comments to the Author: (There are no comments.) ********************************************** Reviewers' Comments to Author: Reviewer: 1 Comments to the Author(s) Dear respected editor Thank you very much for letting me the opportunity to reviews some scientific papers in your valuable journal. Regarding the manuscript under consideration, (entitled: Preparation and regeneration of ironmodified nanofibres for low concentration phosphorus-containing wastewater treatment), the manuscript and the obtained results are interesting and well organized. I suggest this manuscript would be suitable for publication in your respected journal after minor revision. My comments are: Adv. Powder Technol., 23 (2012) 757-760. 2: There are some grammatical errors in the manuscript. Hence, the manuscript should be carefully checked and necessary corrections should be done. 3: In the experimental part (2.1 Chemical reagents), the chemical structure of the used chemicals must be written.

Reviewer: 2
Comments to the Author(s) The manuscript reports on Preparation and regeneration of iron-modified nanofibres for low concentration phosphorus-containing wastewater treatment. Authors are attempted to develop iron-modified nanofibres for the treatment for low concentration phosphorus-containing wastewater treatment. It needs major revision before accepting for publication.
In introduction section lack of literature review is missing, authors should read below relevant reference and consider for citation. Nanophotocatalysis and Environmental Applications, 139-169, 2020. International Journal of Hydrogen Energy, doi.org/10.1016/j.ijhydene.2019.03.149. 2019Nanophotocatalysis and Environmental Applications, 83-105, 2019Polyhedron 120, 169-174, 2016. Proper scale is missing in SEM images, better to provide details in the image.
The Conclusion section is too short, it should be written properly. And also mention like can be reused many times, it is better to mention how many times can be used. English and grammatical errors should be rectified during the revision of the paper.

Reviewer: 3
Comments to the Author(s) How to improve the economy and recycling degree of low concentration phosphorus wastewater treatment is one of the difficulties of municipal domestic wastewater treatment. This paper described the adsorption of low concentration phosphorus from simulated waste water source using bamboo-based nanocellulose fiber loaded with iron hydroxide (Fe(OH)3@CNFs). As an environmentally friendly adsorbent material, it has great potential for application. On the other hand, it can provide technical support for China's continuous improvement of sewage discharge standards, and it can also provide a feasible way for the recovery and utilization of phosphorus resources. 1. There are different kinds cellulose materials in nature, the authors should tell what is the advantage of bamboo compared with others. 2. Loading of metal/metal oxides to carrier material result in decreased surface area and porosity due to void volume blockages. However, what we observed here is a significant increase in surface area after loading of Fe(OH)3 ？ 3.

Dear Editors and Reviewers:
First of all, we would like to thank the anonymous reviewers for their constructive comments to improve our manuscript entitled " Preparation and regeneration of ironmodified nanofibres for low concentration phosphorus-containing wastewater treatment " (ID: RSOS-190764). We really appreciate their precious time and great efforts on reviewing the manuscript. Consequently, we have studied comments carefully and have made correction which we hope meet with approval. Revised portion are marked in red in the paper. The main corrections in the paper and the responds to the reviewer's comments are as flowing: Responds to the reviewer's comments:

Reviewer: 1
Comments to the Author(s) Dear respected editor Thank you very much for letting me the opportunity to reviews some scientific papers in your valuable journal.
Regarding the manuscript under consideration, (entitled: Preparation and regeneration of iron-modified nanofibres for low concentration phosphorus-containing wastewater