Biomass Pyrolysis Technology by Catalytic Fast Pyrolysis, Catalytic Co-Pyrolysis and Microwave-Assisted Pyrolysis: A Review

Round 1

Reviewer 1 Report

The paper entitled “Biomass Pyrolysis Technology by Catalytic Fast Pyrolysis, Catalytic Co- Pyrolysis and Microwave Assisted Pyrolysis: A Review” revises recent advances biomass catalytic pyrolysis. Accordingly, the topic is relevant and of potential interest for Catalysts readers. Moreover, it is in general well written. However, the paper has some weak points and must revised and improved prior considering its publication.

 

The scope and structure of this review should be justified and better defined. Thus, it includes catalytic fast pyrolysis, co-pyrolysis and microwave pyrolysis. Why this differentiated approach regarding microwave pyrolysis? In fact the authors revised studies performed in different reactor design in this paper, why should be considered microwave pyrolysis in an independent section? This decision seems to be unclear. Please justify this decision.

The authors remarked several times in this paper the relevance of fast pyrolysis and catalytic fast pyrolysis and moreover this review is supposed to be centered in fast pyrolysis studies. However several studies analyzed in this review were not carried out under fast pyrolysis conditions. Moreover, the authors did not pay attention to fast pyrolysis technologies in this paper, accordingly, the reviewer suggest including a new section with a briefly description of main fast pyrolysis technologies such as fluidized beds, spouted beds, ablative reactors of fast heating microrecators. In addition their features and their application should be revised.

The authors should avoid the use of abbreviations in the sections titles (CCP, CFP, MAP…).

It could be interesting the incorporation of a new section (or even a table) in which the main features of the catalysts used in biomass pyrolysis are discussed and summarized.

A point that should be improved in this review is the critical evaluation of the results. Thus, the authors merely comment the results obtained in the literature, however, a deeper analysis and evaluation of the results is lacking. Accordingly, the authors should provide some discussion and their own conclusions related with each topic revised in this paper.

Table 1 and Table 2 provide limited information regarding the results obtained in the literature. In fact, target product or result columns information is really poor. The authors should try to include most relevant results in these tables.

The citation style in 3.1 section should be revised:” high-density polyethylene(HDPE), polypropylene(PP), polystyrene(PS)[72-74]. In addition, waste tires and household garbage are used as additives in Co-pyrolysis[75, 76].”

Further attention should be paid to the reaction mechanism in catalytic biomass degradation. In spite of the fact that the authors mentioned in the abstract that this is one of the aims of this review, unfortunately the discussion on reaction mechanism is weak. In the same line the role played by different catalysts acidity and shape selectivity should be deeply analyzed.

The authors should briefly discuss some critical aspects and challenges of catalytic fast pyrolysis such as catalyst deactivation and regeneration or process scale up.

 

 

 

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Dear Authors,

Being a long time involved in pyrolysis chemistry and processes for waste and biomass treatment, I consider you work as an important overview of scietintific and engineering achivement in the field of waste-to-materials_with_added_value conversion technologies. In an whole the paper is written in a very good manner and possesses all features of scientific review. I consider it as a step forward in valorisation of pyrolysis technologies for biomass and other organic materials.

 

Author Response

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Reviewer 3 Report

The manuscript titled “Biomass Pyrolysis Technology by Catalytic Fast Pyrolysis, Catalytic Co- Pyrolysis and Microwave- Assisted Pyrolysis: A Review” presented as review by Junjian Liu, Qidong Hou, Meiting Ju, Peng Ji, Qingmei Sun and Weizun Li is a contribution of a wellknown topic with interest for catalytic research community and, in my opinion, should be published.

I suggest to revise the typewritten in:

• Line 169, “HZSM-5 Catalyst”
• Line 188, “Tan et al. Carried”
• Line 194 “Gautam et al. Studied”
• Line 198 “]. Zhang et al. Introduced “ and “CeO2”
• Line 247 “LDPE ratoio in the”
• Line 261 “Xue et al. Studied”
• Line 294 “can reduc the”
• Line 296 “tires, Results indicated”
• Line 325 “found The yield”
• Line 353 “with Cao catalyst,”

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have revised and improved the paper entitled “Biomass Pyrolysis Technology by Catalytic Fast Pyrolysis, Catalytic Co- Pyrolysis and Microwave-Assisted Pyrolysis: A Review”. The authors have partially considered reviewer suggestions and some modifications were carried out. However certain points should be further improved prior publication.

The considerations regarding catalytic fast pyrolysis remain unclear, as previously mentioned several studies revised in this study were not carried out under fast pyrolysis conditions.

The discussion of the challenges associated to this processes should include additional aspects, not only catalysts deactivation.

Author Response

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