Enzyme-assisted mechanical grinding for cellulose nanofibers from bagasse: energy consumption and nanofiber characteristics
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Bagasse fibers are smaller and have more hemicellulose than softwood fibers, which is expected to require less mechanical energy in cellulose nanofiber production as small size and hemicellulose benefit the disintegration of fibrils during a mechanical process. Both bagasse fibers and softwood fibers were used in this investigation for producing nanofibers with enzyme pretreatment followed by mechanical grinding. Results showed that nanofibers from bagasse had more uniform diameters about 9 nm, and the films made from them were more transparent. Grinding energy consumption of bagasse fibers was significantly lower than softwood, by 7.31%, and enzyme pretreatment further improved the energy efficiency, by 59.71%, and the yield of nanofibers, by 30.57%. The mechanical strength and thermal stability of nanofiber films from bagasse fibers were similar with that from softwood fibers. The results support the idea that bagasse, a waste or byproduct from sugar industry can be a promising alternative for nanofiber production.
KeywordsBagasse cellulose nanofibers Energy consumption Enzyme pretreatment Ultrafine grinding
The authors thank the Project for Graduate Study Overseas of Guangxi University and China Scholarship Council under Grant No. 201706660011 for research assistance. The research is sponsored by the Innovation Project of Guangxi Graduate Education (YCBZ2018016), the National Natural Science Foundation of China (21766002), the Scientific Research Foundation of Guangxi University (XTZ140551), and the Foundation of Guangxi Key Laboratory of Clean Pulp &Papermaking and Pollution Control (KF201606 and ZR201603).
- Bian H, Gao Y, Yang Y, Fang G, Dai H (2018b) Improving cellulose nanofibrillation of waste wheat straw using the combined methods of prewashing, p-toluenesulfonic acid hydrolysis, disk grinding, and endoglucanase post-treatment. Bioresour Technol 256:321–327. https://doi.org/10.1016/j.biortech.2018.02.038 CrossRefPubMedGoogle Scholar
- Rajinipriya M, Nagalakshmaiah M, Robert M, Elkoun S (2018) Importance of agricultural and industrial waste in the field of nanocellulose and recent industrial developments of wood based nanocellulose: a Review. ASC Sustain Chem Eng 6:2807–2828. https://doi.org/10.1021/acssuschemeng.7b03437 CrossRefGoogle Scholar
- Rambabu N, Panthapulakkal S, Sain M, Dalai AK (2016) Production of nanocellulose fibers from pinecone biomass: evaluation and optimization of chemical and mechanical treatment conditions on mechanical properties of nanocellulose films. Ind Crop Prod 83:746–754. https://doi.org/10.1016/j.indcrop.2015.11.083 CrossRefGoogle Scholar
- Sacui IA et al (2014) Comparison of the properties of cellulose nanocrystals and cellulose nanofibrils isolated from bacteria, tunicate, and wood processed using acid, enzymatic, mechanical, and oxidative methods. ACS Appl Mater Inter 6:6127–6138. https://doi.org/10.1021/am500359f CrossRefGoogle Scholar
- Saelee K, Yingkamhaeng N, Nimchua T, Sukyai P (2016a) An environmentally friendly xylanase-assisted pretreatment for cellulose nanofibrils isolation from sugarcane bagasse by high-pressure homogenization. Ind Crops Prod 82:149–160. https://doi.org/10.1016/j.indcrop.2015.11.064 CrossRefGoogle Scholar
- Segal L, Creely JJ, Martin AE, Conrad CM (1959) An empirical method for estimating the degree of crystallinity of native cellulose using the X-Ray diffractometer. RES J 29:786–794Google Scholar