ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Choline chloride-based deep eutectic solvents for efficient delignification of Bambusa bambos in bio-refinery applications

Remi Ramesh, Arya Nair, Aakash Jayavel, Kiruthika Sathiasivan, Mathur Rajesh, Shri Ramaswamy, and Krishnamurthi Tamilarasan

Department of Chemical Engineering, SRM Institute of Science and Technology, Chennai, India

E-mail: tamilbio@gmail.com

Received: 2 May 2020  Accepted: 18 June 2020

Abstract:

The use of choline chloride–oxalic acid (CO) and choline chloride–urea (CU) green solvents as mediator for delignification of Bambusa bambos stem (BS) has been studied. The optimal delignification of BS obtained at 120 °C and 4 h of DESs (deep eutectic solvents) treatment process. The morphological structure of raw BS and treated BS was analyzed by SEM, XRD, and FTIR. The results showed that the crystallinity index increased from 43.8 in raw BS, to 44.3%, and CUT-BS and 46.4 in COT-BS. The surface elemental composition of BS was estimated by photoelectron spectroscopy (XPS). The carbon and oxygen elemental contents in the biomass surface were determined by XPS survey, C1s, and O1s spectra. The delignification using CO system (25.4%) more easily digested the BS biomass compared to CU system (19.4%). The use of acid DES can be an effective pretreatment process compared to basic treatment processes for biomass fractionation in bio-refinery applications.

Keywords: Green solvent; Delignification; Crystallinity index; Elemental composition

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-020-01259-2

Chemical Papers 74 (12) 4533–4545 (2020)