Fractional Condensation of Fast Pyrolysis Bio-Oil to Improve Biocrude Quality towards Alternative Fuels Production

Round 1

Reviewer 1 Report

The manuscript entitled “Fractional condensation of Fast Pyrolysis Bio Oil to improve biocrude quality towards alternative fuels production” present an interesting approach to improve biocrude quality. The result is meaningful. I think major revision is needed.

 

1. Overall, the text is tedious. In the introduction, the recent progress and the main technical bottleneck should be summarized. In the experimental section, there’re so many discussions. In the conclusion, the main conclusion should be summarized, instead of repeating the discussion.
2. The abbreviation should be defined when they appear first time. Such as TRL, EU. There’re some unprofessional terminology, such as lignocellulosic fast pyrolysis bio-oils.
3. The subscripts are not right.

 

4. The data in table 1 is obtained from literature. Even if same kind of feedstock is used, it’s better to test their composition since the composition of biomass from different source is different.

 

5. In figure 6, the standard deviation of data should be provided.
6. The authors can refer to several comprehensive review articles on biomass (DOI: 10.1039/D0GC02770G) and plastic wastes (DOI: 10.1016/j.xcrp.2021.100514)

Author Response

Dear reviewer, thanks for your comments. Here enclosed our replies.

Author Response File: Author Response.docx

Reviewer 2 Report

The manuscript studies the fractional condensation of fast pyrolysis oil to facilitate its valorization.

This is a very attractive topic on account of the great interest of biomass bio-oil as a fuel and raw material. Furthermore, the experimental equipment used for condensation is very adequate and explained in detail, which will be very interesting for a good number of researchers.

However, some improvements should be made in the manuscript to deserve publication, especially in discussion and conclusions sections that are excessively terse. The improvements to be developed are the following:

• The justification of the technology for fractional distillation of volatiles coming from pyrolysis would be strengthen by emphasizing the enormous difficulty of bio-oil distillation, in which the deposition of pyrolytic lignin takes place.
• There are several reviews that gather the bio-oil valorization routes (Valle et al., J. Chem. Technol. Biotechnol., 94 (2019) 670-689), in which the authors do not give the importance that deserves the steam reforming for the production of H2.
• The discussion section deals very superficially with the suitability of the composition of each bio-oil fraction for each valorization route. This relationship can be improved by taking into account the different composition of the condensed fractions and their particular interest for the different routes: 1) Production of commodities (such as olefins and aromatics) over zeolites; 2) Production of H2 by steam or dry reforming (Zhao et al., Chem. eng. Technol. 43 (2020) 625-640; 3) Hydrodeoxygenation (Cordero-Lanzac et al., Appl. Catal. B: environ, 239 (2018) 513-524); 4) Co-feeding into FCC units (Pinho et al., Fuel Process. Technol. 229 (2022) 107176). The usefulness of the results to facilitate the valorization of bio-oil is the main challenge of the manuscript and must be developed according to the literature in which these routes are studied. This specific literature would have much more value in the manuscript than the references providing general information about fluidization and other topics that are not studied in the manuscript.
• The conclusions section should reflect specific results since it is written in a very general way, which is not appropriate for an article of a technological nature.

The manuscript is of great quality, but it requires a moderate revision attending to the aforementioned suggestions. 

Author Response

Dear reviewer, thanks for your comments. Here attached our replies.

Author Response File: Author Response.docx