A COMPREHENSIVE METHOD FOR CONCURRENT RECOVERY OF CELLULOSE, NANOCELLULOSE AND LIGNIN FROM DURIAN PEEL: A SUSTAINABLE APPROACH

Abstract

Recovering valuable components from agricultural waste is an emerging focus in sustainable development. This study investigates using durian peel (DP) as a raw material for extracting cellulose, nanocellulose (NC), and lignin. The process involves four key stages: (1) pre-treatment, (2) cellulose extraction using 15% (w/v) sodium hydroxide at 100 °C for 2 hours with a ratio of 20/1 mL/g, followed by bleaching with 15% (w/v) hydrogen peroxide overnight, (3) lignin recovery by acidifying the black liquor to pH 1 with concentrated sulfuric acid, and (4) NC extraction through hydrolysis in 64% (v/v) sulfuric acid at 45 °C for 3 hours with a ratio of 20/1 mL/g, followed by neutralization, grinding, centrifugation, filtration, and ultrasonication. The recovery yields were 11.92% for lignin, 54.33% for crude cellulose, 36.03% for pure cellulose, and 29.18% for NC. The NC obtained, characterized as cellulose nanofibrils (CNF), had an average diameter of 114 nm, with 62.23% of particles below 100 nm and 100% below 200 nm. The crystallinity indices were 32.29% for NC and 40.08% for cellulose, while lignin exhibited an amorphous structure. Thermal analysis (TGA) revealed that cellulose degrades more than nanocellulose, indicating that nanocellulose has higher thermal stability. Lignin exhibits excellent thermal stability up to 600 °C, making it suitable for hightemperature applications. These results underscore the potential of DP as a source of valuable bioproducts, including lignin, cellulose, and NC, for diverse industrial applications.