Recent Advances in the Bioconversion of Waste Straw Biomass with Steam Explosion Technique: A Comprehensive Review
, Hongzhao Li 1,2, Limei Chen 3, Tianhong Fu 1,4,5, Bingbing Tang 6, Yongzhou Hao 1,2, Jing Li 1, Zheng Li 1, Bangxi Zhang 5, Qing Chen 6, Chengrong Nie 2, Zi-Yi You 7, Chung-Yu Guan 7,* and Yutao Peng 8,*Round 1
Reviewer 1 Report
The authors provided a review on advances in bioconversion of waste straw biomass using steam explosion techniques. Overall, the literature review was excellent with most significant works included. However, the writing needs improvement and more depth in the discussion may be required. Authors should also note that there are many similar reviews already published, hence authors should highlight the novelty in this work compared to others. Below are my suggestions/comments:
1. Abstract: "robust molecular structure limits..." - word choice
2. P2 - "non-covalent bonds" - what are they exactly?
3. P2 - "structure lignin" - restructure? break down?
4. P2 - "chemical methods can easily cause environmental pollution." - sweeping sentence - this means that all laboratories are causing environmental pollution
5. P2 - how does acidic environments break down covalent bonds?
6. P3 - prevent the overuse of chemical fertilizers - I don't think this is correct
7. P4 - straw is "stubborn" - word choice
8. P4 - "Generally speaking,...." - sentence is confusing, pls rewrite.
9. P4 - "Sugarcane is the most widely planted crop..." - reference?
10. P4 - percentages in 1 dp is sufficient - expected to vary
11. P5 - TAPPI standard in full?
12. P5 - define "packing period"
13. P5 - "compared to other treatments..." - such as? show examples of other treatment
14. P6 - "enhanced by reduced ash and extracts" - what is extract?
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
General comments:
Current article focused on recent advances of utilizing steam explosion as pretreatment method for promoting diverse straw biomass bioconversion processes, e.g., productions of biofuel, chemicals, agricultural products and etc. Detailed introduction on corresponding processes and mechanisms were also introduced in detail. Current review helps to give full and deep insights into the steam explosion for straw biomass conversion and proposed good future recommendations for developing steam explosion utilized for environment protection and green energy development. To further improve the structure, language and content of this review before its publication, the following issues should be carefully addressed.
Specific comments:
1. “In recent years, some pretreatment techniques have been developed to structure lignin”: This sentence should be improved, the sentence meaning were not clear.
2. “The physical method has high energy consumption and a low lignin removal rate”, the authors should know that the steam explosion technique belong to physical technique, herein, the authors should specify the physical method here.
3. “the decomposition of part of hemicellulose” should be changed to “the decomposition of partial hemicellulose”; “These studies show that” should be changed to “It was reported that”.
4. Fig. 3A and Fig. 3B were less relevant to current review topic, these figures can be substituted with production of diverse straw resource.
5. The title of section 3 should be changed to “Characteristics of steam explosion treated straw biomass”.
6. “the steam temperature and residence time”, the authors should introduce the ranges of the steam temperature and residence time, what are the common ranges of the steam temperature and residence time. In current section, other critical characteristics, e.g., specific surface area, pore volume and etc. should be included.
7. In terms of section 4, the authors can propose a diagram showing how the steam explosion process of the straw biomass, in which it’s better include the key characteristics.
8. “Herein, SE is widely used as a pretreatment method for straw biomass bioconversion which was separately introduced below.”, this sentence should be revised to highlight the critical advantages of SE in treating straw biomass and valorization.
9. In section 4.1 to 4.6, separate diagram describing how the SE play efficient roles in diverse straw valorization ways.
10. Future prospects should be introduced in order, and the advantages of SE treated straw biomass in producing engineered materials can be included.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The authors have revised the manuscript satisfactorily.
Minor comment:
Abstract: "stubborn" - replaced with "rigid"
