Recovery of cellulose fibers from oil palm empty fruit bunch for pulp and paper using green delignification approach.

• Hydrogen bonds formed in the LTTMs enabled the removal of lignin from EFB. • Clear separation of precipitated lignin was observed in EFB strands after washing. • EFB powder showed stronger molecular bonding of pulp than EFB strands. • Paper formed from cactus based LTTMs-delignified EFB had less void space and pores. The aim of this work was to recover the cellulose fibers from EFB using low-transition-temperature-mixtures (LTTMs) as a green delignification approach. The hydrogen bonding of LTTMs observed in 1H NMR tends to disrupt the three-dimensional structure of lignin and further remove the lignin from EFB. Delignification process of EFB strands and EFB powder were performed using standard l -malic acid and cactus malic acid-LTTMs. The recovered cactus malic acid-LTTMs showed higher glucose concentration of 8.07 mg/mL than the recovered l -malic acid LTTMs (4.15 mg/mL). This implies that cactus malic acid-LTTMs had higher delignification efficiency which led to higher amount of cellulose hydrolyzed into glucose. The cactus malic acid-LTTMs-delignified EFB was the most feasible fibers for making paper due to its lowest kappa number of 69.84. The LTTMs-delignified EFB has great potential to be used for making specialty papers in pulp and paper industry. [ABSTRACT FROM AUTHOR]