Abstract
Waste biomass (agave bagasse) and native birch wood were used as raw materials for a novel fractionation and derivation process to produce cellulose acetates (CAs). During the first stage of the fractionation process, a significant amount of hemicelluloses and lignin were dissolved from the biomass using a natural deep eutectic solvent (NADES) that consisted of a mixture of choline chloride and lactic acid with the molar ratio of 1:9. Then, the residual solid material was delignified by bleaching it with a mixture of acetic acid and sodium chlorite. The fractionation process generated differently purified pulps (celluloses) which were converted to CAs. The crystallinity index, polymerization degree, chemical composition, and thermal properties of the differently purified pulps and CAs were analyzed to evaluate the efficacy of the acetylation process and to characterize the CAs. The chemical derivation of the differently purified cellulose samples generated CAs with different degrees of substitution (DSs). The more purified the cellulose sample was, the higher its DS was. Moreover, some differences were observed between the acetylation efficiencies of birch and agave bagasse. Typically, cellulose purified from birch by treating it with NADES followed by bleaching was acetylated more completely (DS = 2.94) than that derived from agave bagasse (DS = 2.45). These results revealed that using green solvents, such as NADES, to treat both agave bagasse (waste biomass) and birch wood, allowed pure fractions to be obtained from biomass, and thus, biomass could be valorized into products such as CAs, which present a wide range of applications.
Highlights
Lignocellulosic biomasses have emerged as promising feedstock for the development of value-added products, and their abundancy, renewability, and biodegradability are some of their most attractive characteristics
Cellulose purified from birch by treating it with natural deep eutectic solvent (NADES) followed by bleaching was acetylated more completely (DS = 2.94) than that derived from agave bagasse (DS = 2.45). These results revealed that using green solvents, such as NADES, to treat both agave bagasse and birch wood, allowed pure fractions to be obtained from biomass, and biomass could be valorized into products
The following nomenclature was used for the pulps : Agave N and Birch N denote the NADESpretreated agave and birch pulps, respectively; Agave NB and Birch NB denote the NADES-pretreated and acid-chlorite-delignified agave and birch pulps, respectively; Agave NA and Birch NA denote the NADES-pretreated and acetylated pulps derived from agave bagasse and birch chips, respectively; and Agave NBA and Birch NBA denote the NADESpretreated, acid-chlorite-delignified, and acetylated pulps from agave bagasse and birch chips, respectively
Summary
Lignocellulosic biomasses have emerged as promising feedstock for the development of value-added products, and their abundancy, renewability, and biodegradability are some of their most attractive characteristics. Corn stover, sugarcane bagasse, cornhusk, cotton, oil palm empty fruit bunch, agave bagasse, rice husk, cereal straw, and different types of wood mainly comprise cellulose, hemicelluloses, and lignin, and have been used as raw materials for the production of chemicals, energy, and various materials. Cellulose is the most abundant natural polymer on earth and the predominant component of lignocellulose (Wan Daud and Djuned 2015; Chen et al 2016; Ruiz-Cuilty et al 2018; Candido et al 2017). Cellulose has been typically described as a linear chain of bD-glucopyranosyl units linked by 1–4-b-glucosidic bonds. Cellulose can be chemically modified to obtain materials with different physical and chemical properties for specific purposes
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
