Production of High-Porosity Biochar from Rice Husk by the Microwave Pyrolysis Process

Round 1

Reviewer 1 Report

Comments for author File: Comments.pdf

Author Response

Q1. Are the gases produced during pyrolysis removed from the reactor? If so, please mark in the drawing the place of outlet of gaseous products from the system.

Reply: As suggested by the reviewer, the “outlet (to hood)” has been coded as number 6 in Figure 1.

Q2. A few editorial comments/errors.

Reply: RAs suggested by the reviewer, these comments/errors have been corrected to mark the red color in the revised manuscript.

Q3. The quality of Figure 7 and Figure 8 requires improvement.

Reply: As suggested by the reviewer, the two figures have been properly improved to make them clear.

Q4. Lines 268-272, please revise them properly.

Reply: As suggested by the reviewer, the description about the comparison between Figure 6(a) and Figure 6(b) has been revised to make it differentially.

“…………………  Figure 6 revealed the SEM images of RH and BC-RH-1000W-5M at different magnifications (×500 and ×1000), showing similar shaped surface [41].  However, the surface of RH-based biochar has become more corrugated after microwave pyrolysis, which can be seen in Figure 6(b).   ………………………….”

Reviewer 2 Report

In this contribution, a rigorous and detailed study is carried out on the most suitable synthesis conditions (assisted by MW) for obtaining porous biochar from rice husk.

Obtaining biochar from rice husks has been known for a long time. This does not mean that it is less interesting and more so when we think about chemical strategies framed in the circular economy. One of the relatively novel aspects is the use of microwave treatments instead of conventional oven processes. In fact, in the introduction, the authors cite three references in which MW is used to obtain biochar from rice husk. They could include a very recent review article on the topic (https://doi.org/10.1016/j.jaap.2023.106094). In general, the literature on the specific aspect (biochar from rice husk via MW pyrolysis) could be more up-to-date.

On the other hand, a comparison of the characteristics of the biochar obtained in relation to previous works in the bibliography does not appear in the manuscript.

Author Response

Q1. In fact, in the introduction, the authors cite three references in which MW is used to obtain biochar from rice husk. They could include a very recent review article on the topic (https://doi.org/10.1016/j.jaap.2023.106094). In general, the literature on the specific aspect (biochar from rice husk via MW pyrolysis) could be more up-to-date.

Reply: In fact, the review article on the topic (https://doi.org/10.1016/j.jaap.2023.106094)has been included in the manuscript (Ref. 33).  As suggested by the reviewer, the literature on the specific aspect (biochar from rice husk via MW pyrolysis) was further updated in the second paragraph of the Introduction by marking red color.

Q2. A comparison of the characteristics of the biochar obtained in relation to previous works in the bibliography does not appear in the manuscript.

Reply: As suggested by the reviewer, a comparison of the characteristics of the biochar obtained in relation to previous works in the bibliography has been added to the Sec. 3.3, making it differential (by marking red color).

Round 2

Reviewer 2 Report

I consider that after the changes realized by the authors according to the reviewer suggestion, this contribution can to be published without additional changes.

Author Response

Q1. I consider that after the changes realized by the authors according to the reviewer suggestion, this contribution can to be published without additional changes.

Reply: Thanks for the positive comment by the reviewer.