A Systematic Review on the Synthesis of Silicon Carbide: An Alternative Approach to Valorisation of Residual Municipal Solid Waste

Round 1

Reviewer 1 Report

The article is devoted to an interesting and actual topic of summarizing the accumulated data on the synthesis methods, properties, and application of various silicon carbide particles. This is a relevant and important theme, but the presented work requires some revision, and expansion, because. several aspects are missing, and part of the description is redundant and does not correspond to the stated topic. It should be published after Major revision.

1) The introduction is too redundant; it should be rewritten to eliminate the redundant and expand the information in the Manuscript. Here are just a few examples, as by and large, the first two pages can be replaced with a couple of introductory sentences.

For example:

1.1) In lines 25-35 and 40-49, the whole paragraphs are devoted to the description of waste types, which is very far from the topic of the work and can be summarized and written shorter.

1.2) Lines 91-96 The description of the transponder and its functions are completely irrelevant to the topic of the work. This should be removed.

2) In the second section (Structure of silicon carbide), the forms of silicon carbide and their main properties are revealed, this section lacks the results of the analysis of the formed structures (IR, Raman spectroscopy, X-ray diffraction, etc.) with a description of the characteristics of silicon carbide as in the original form, as well as in the composites. Perhaps the methods of silicon carbide analysis should be moved to a separate section. This is very relevant to this topic, which should be described.

3) Line 445 The phrase is incorrect. As a result of TEOS hydrolysis, oligosiloxanes or silicon oxide are formed, which forms silicon carbide only during subsequent high-temperature sintering.

4) Line 467 The meaning of this sentence remained unclear to me. How is the evolution of plants related to silicon carbide production?

5) Line 541 SiC is itself chemically inert. What exactly is the morphology and composition of such membranes? This should be described in more detail.

6) Line 562 How exactly did Au improve the catalytic properties of silicon carbide?

7) There are no references to many important sections and works. Here are just a few of them as an example:

7.1) The founder of the production of silicon carbide was prof. Acheson. Later the process of reducing silicon oxide in excess carbon to carbide was named after him:

Acheson EG. Carborundum: Its history, manufacture, and uses. Journal of the Franklin Institute. 1893 Oct 1;136(4):279-89.

7.2) There is no section describing the silicon carbide production from polycarbosilanes:

Schilling Jr, C.L., Wesson, J.P. and Williams, T.C., 1983. Polycarbosilane precursors for silicon carbide. In Journal of Polymer Science: Polymer Symposia (Vol. 70, No. 1, pp. 121-128). New York: Wiley Subscription Services, Inc., A Wiley Company.

7.3) There is a lack of a section devoted to methods for obtaining SiC of various shapes (fibers, nanofibers, particles, whiskers, etc.):

Particles (the Authors have a Sol-gel section, but there is only one link to the section):

Omidi Z., Ghasemi A., Bakhshi S. R. Synthesis and characterization of SiC ultrafine particles by means of sol-gel and carbothermal reduction methods //Ceramics International. – 2015. – Т. 41. – №. 4. – С. 5779-5784.

Ko S. M. et al. Synthesis of SiC nano-powder from organic precursors using RF inductively coupled thermal plasma //Ceramics international. – 2012. – Т. 38. – №. 3. – С. 1959-1963.

Whiskers:

Chrysanthou A., Grieveson P., Jha A. Formation of silicon carbide whiskers and their microstructure //Journal of materials science. – 1991. – Т. 26. – №. 13. – С. 3463-3476.

Nanowires:

Meng G. W. et al. Synthesis of β-SiC nanowires with SiO2 wrappers //Nanostructured Materials. – 1999. – Т. 12. – №. 5-8. – С. 1003-1006.

Fibers:

Wang P. et al. A review of third generation SiC fibers and SiCf/SiC composites //Journal of Materials Science & Technology. – 2019. – Т. 35. – №. 12. – С. 2743-2750.

Hou X. et al. Characterization and properties of silicon carbide fibers with self-standing membrane structure //Journal of Alloys and Compounds. – 2015. – Т. 649. – С. 135-141.

By the way, in addition to the sol-gel method from TEOS, carbide is also obtained from other siloxanes, such as PDMS:

Camino G., Lomakin S. M., Lazzari M. Polydimethylsiloxane thermal degradation Part 1. Kinetic aspects //Polymer. – 2001. – Т. 42. – №. 6. – С. 2395-2402.

7.4) The issue of obtaining silicon carbide particles in carbon or other inorganic matrices in situ is not consecrated at all, for example:

Makarov, I.S., Golova, L.K., Bondarenko, G.N., Skvortsov, I.Y., Berkovich, A.K., Bermeshev, M.V. and Mironova, M.V., 2017. Carbon—Silicon-Carbide Fibers Prepared from Solid Solutions of Cellulose in N-Methylmorpholine-N-Oxide with Added Tetraethoxysilane. Fibre Chemistry, 49(4), pp.231-236.

Makarov, I.S., Golova, L.K., Mironova, M.V., Vinogradov, M.I., Bermeshev, M.V., Berkovich, A.K. and Kulichikhin, V.G., 2018. Structural and Morphological Features of Carbon—Silicon-Carbide Fibers Based on Cellulose and Triethoxyvinylsilane. Fibre Chemistry, 50(2), pp.79-84.

Zhang, G.J. and Ohji, T., 2001. In situ reaction synthesis of silicon carbide–boron nitride composites. Journal of the American Ceramic Society, 84(7), pp.1475-1479.

I recommend adding at least these links to the works in the relevant sections with their descriptions.

8) Most importantly, there is absolutely no information on obtaining silicon carbide from waste. Thus, you need to add the appropriate section or change the name and part of the first section.

Carbon black is a large-tonnage cheap product, it seems to me that the production of carbide from a mixture of carbon black with silica (for example) from an economic point of view, taking into account the stages of subsequent purification, size factor, and sample preparation, is much more profitable than waste processing.

Author Response

We thank the reviewers for their suggestions and comments. We have revised the manuscripts accordingly and incorporated suggested changes. Additionally, we have corrected grammatical and semantic errors prevalent throughout the manuscript. All changes have been highlighted for the reviewer’s consideration.

Reviewer #1:

1. “The introduction is too redundant; it should be rewritten to eliminate the redundant and expand the information in the Manuscript. Here are just a few examples, as by and large, the first two pages can be replaced with a couple of introductory sentences.”

Response: We are grateful for the valuable inputs on the manuscript and we have revised the manuscript accordingly. We have added instances of environmental degradation were added to the manuscript.

1.1 “In lines 25-35 and 40-49, the whole paragraphs are devoted to the description of waste types, which is very far from the topic of the work and can be summarized and written shorter.”

Response: We apologise for straying off-topic in this section. We have revamped the introduction accordingly and incorporated changes to alleviate its overall quality.

• “Lines 91-96 The description of the transponder and its functions are completely irrelevant to the topic of the work. This should be removed.”

Response: We acknowledge the concern raised and, we have removed this portion, as suggested by the reviewer.

• “In the second section (Structure of silicon carbide), the forms of silicon carbide and their main properties are revealed, this section lacks the results of the analysis of the formed structures (IR, Raman spectroscopy, X-ray diffraction, etc.) with a description of the characteristics of silicon carbide as in the original form, as well as in the composites. Perhaps the methods of silicon carbide analysis should be moved to a separate section. This is very relevant to this topic, which should be described.”

Response: In this review the main focus is about the synthesis, properties and its corresponding applications. We also believe a detailed study with extensive results from characterisation of different samples will be a good basis for a future study. Hence, we have refrained from including data regarding the same. Thank you so much for the suggestion.

• “Line 445 The phrase is incorrect. As a result of TEOS hydrolysis, oligosiloxanes or silicon oxide are formed, which forms silicon carbide only during subsequent high-temperature sintering.”

Response: We understand the concern raised and we have altered the write-up to explain it in a more apt manner.

• “Line 467 The meaning of this sentence remained unclear to me. How is the evolution of plants related to silicon carbide production?”

Response: Thank you for pointing out the error and we apologise for any inconvenience caused to the reviewers. We have removed this statement from the section – additionally, we have also added the steps followed by Chakrabarti et al for converting Si-SiC ceramics into SiC ceramics at 1200°C in the presence of oxygen using the parts of monocotyledenous plants.

• “Line 541 SiC is itself chemically inert. What exactly is the morphology and composition of such membranes? This should be described in more detail.”

Response: We have updated the details pertaining to the morphology and composition of such membranes. Thank you for pointing it out.

• “Line 562 How exactly did Au improve the catalytic properties of silicon carbide?”

Response: In our literature survey, we recorded studies revealing enhancement  in photocatalytic and photoelectrochemical performances of SiC via undergoing cyclic tests.

• “There are no references to many important sections and works. Here are just a few of them as an example:”

Response: We have updated the following references in the suggested sections:

7.1 - Acheson EG. Carborundum: Its history, manufacture, and uses. Journal of the Franklin Institute. 1893 Oct 1;136(4):279-89.

7.2 - Schilling Jr, C.L., Wesson, J.P. and Williams, T.C., 1983. Polycarbosilane precursors for silicon carbide. In Journal of Polymer Science: Polymer Symposia (Vol. 70, No. 1, pp. 121-128). New York: Wiley Subscription Services, Inc., A Wiley Company.

7.3 - Omidi Z., Ghasemi A., Bakhshi S. R. Synthesis and characterization of SiC ultrafine particles by means of sol-gel and carbothermal reduction methods //Ceramics International. – 2015. – Т. 41. – №. 4. – С. 5779-5784.

- Ko S. M. et al. Synthesis of SiC nano-powder from organic precursors using RF inductively coupled thermal plasma //Ceramics international. – 2012. – Т. 38. – №. 3. – С. 1959-1963.

Whiskers:

- Chrysanthou A., Grieveson P., Jha A. Formation of silicon carbide whiskers and their microstructure //Journal of materials science. – 1991. – Т. 26. – №. 13. – С. 3463-3476.

Nanowires:

- Meng G. W. et al. Synthesis of β-SiC nanowires with SiO2 wrappers //Nanostructured Materials. – 1999. – Т. 12. – №. 5-8. – С. 1003-1006.

Fibers:

- Wang P. et al. A review of third generation SiC fibers and SiCf/SiC composites //Journal of Materials Science & Technology. – 2019. – Т. 35. – №. 12. – С. 2743-2750.

7.4 - Makarov, I.S., Golova, L.K., Bondarenko, G.N., Skvortsov, I.Y., Berkovich, A.K., Bermeshev, M.V. and Mironova, M.V., 2017. Carbon—Silicon-Carbide Fibers Prepared from Solid Solutions of Cellulose in N-Methylmorpholine-N-Oxide with Added Tetraethoxysilane. Fibre Chemistry, 49(4), pp.231-236.

- Makarov, I.S., Golova, L.K., Mironova, M.V., Vinogradov, M.I., Bermeshev, M.V., Berkovich, A.K. and Kulichikhin, V.G., 2018. Structural and Morphological Features of Carbon—Silicon-Carbide Fibers Based on Cellulose and Triethoxyvinylsilane. Fibre Chemistry, 50(2), pp.79-84.

- Zhang, G.J. and Ohji, T., 2001. In situ reaction synthesis of silicon carbide–boron nitride composites. Journal of the American Ceramic Society, 84(7), pp.1475-1479

• “Most importantly, there is absolutely no information on obtaining silicon carbide from waste. Thus, you need to add the appropriate section or change the name and part of the first section.”

Response: To our understanding, it seems that the production of carbide from a mixture of carbon black with silica (for example) from an economic point of view is much more profitable than waste processing, taking into account the stages of subsequent purification, size factor, and sample preparation. Hence, we opted out of mentioning direct extraction of SiC from waste.

Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript reviewed recent progress of SiC, which may be synthesized from the residual of municipal solid waste. It can be accepted after a minor revision:

1. The article emphasized the properties of SiC, but how to synthesize SiC seems not fully discussed, especially how it can be fabricated from a MSW, including its pre-treatment of the MSW.

and,

2. How to control the quality of the SiC products is not reviewed, because of MSW contained impurities.

In addition,

3. This paper will be collected in “Section of Biological Processes and Systems” (Special Issue: Sustainable Bioprocessing in Post COVID-19 Era), but rather than the Biological Processes it seems much more suitable for the section of "Sustainable Processes (Special Issue: State of the Art of Waste Utilization and Resource Recovery)" since it discusses the valorization of residual municipal solid waste.

Author Response

We thank the reviewers for their suggestions and comments. We have revised the manuscripts accordingly and incorporated suggested changes. Additionally, we have corrected grammatical and semantic errors prevalent throughout the manuscript. All changes have been highlighted for the reviewer’s consideration.

Reviewer 2 – Comments

1. “The article emphasized the properties of SiC, but how to synthesize SiC seems not fully discussed, especially how it can be fabricated from a MSW, including its pre-treatment of the MSW.”

Response: Thank you for the insightful suggestion. We have included a separate section focusing on other synthesis techniques that has five different subdivisions. Please refer to section 3.15 with the following subdivisions:

3.15.1. Synthesis of nanoparticles of SiC,

3.15.2. Synthesis of nanowhiskers of SiC,

3.15.3. Synthesis of nanowires of SiC,

3.15.4. Synthesis of nanofibers of SiC,

3.15.5. Synthesis of SiC using polycarbosilane and,

3.15.6. Synthesis of SiC using insitu synthesis.

2. “How to control the quality of the SiC products is not reviewed, because of MSW contained impurities.”

Response: We acknowledge the concern raised and, we have included a separate section that focuses on the treatment approaches (4.1. Thermal treatment, 4.2. Acid leaching and 4.3. Floatation) to purify silicon carbide nanoparticles. The silicon purity has also been discussed in some instances because they are used as a feedstock for the synthesis of silicon carbide.

3. “This paper will be collected in “Section of Biological Processes and Systems” (Special Issue: Sustainable Bioprocessing in Post COVID-19 Era), but rather than the Biological Processes it seems much more suitable for the section of "Sustainable Processes (Special Issue: State of the Art of Waste Utilization and Resource Recovery)" since it discusses the valorization of residual municipal solid waste.”

Response: Thank you for the suggestion and we have reviewed the suggested journal. However, we would prefer to adhere to our initial choice of Special Issue. Albeit there is a prevalent sustainable angle to our manuscript, the synthesis pathways for silicon carbide discussed in our study holds considerable relevance to the sustainable bioprocessing. Hence, we would prefer to have it collected under “Sustainable bioprocessing in Post COVID 19 Era”.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The manuscript has been improved, but still there is some remarks:

1)     I still think that first paragraph is not related to the topic of the work.

2)     I highly recommended addition of a description for 3.15 section.

3)     Also, I think that only 1-2 references to a section is not enough for a review paper. Descriptions should be expanded and generalized.

4)     It is also strange that the authors did not add a link to the original work of Acheson, who discovered the process of obtaining silicon carbide.

5)     There are lot of misprints and writing problems in the text, like in Line 533, where “mol.L–1” is written instead mol×L^–1; absence a space between number and °С, etc.

Author Response

Reviewer 1

Comments and Suggestions for Authors

The manuscript has been improved, but still there is some remarks:

1)     I still think that first paragraph is not related to the topic of the work.

We are grateful for the valuable inputs, and we have removed the excerpt from the manuscript.

2)     I highly recommended addition of a description for 3.15 section.

We apologize for not describing the section in an apt manner. We have included content to the section and added relevant references to further elucidate the concepts.

3)     Also, I think that only 1-2 references to a section is not enough for a review paper. Descriptions should be expanded and generalised.

We understand the concerned raised and hence, 22 new references have been included and cited throughout the manuscript. Thank you for your valuable suggesting.

4)     It is also strange that the authors did not add a link to the original work of Acheson, who discovered the process of obtaining silicon carbide.

We acknowledge the issue raised and we have incorporated the reference as [4].

5)     There are lot of misprints and writing problems in the text, like in Line 533, where “mol.L–1” is written instead mol×L–1; absence a space between number and °С, etc.

We extend our gratitude for pointing out the misprints. All the following changes have been corrected throughout the manuscript:

1. The space was added between the number and Å.
2. The power value was changed from normal to superscript.

Author Response File: Author Response.docx