Hydrothermal Liquefaction of Cellulose in the Presence of Sodium Fluoride-Doped Alumina Catalyst

Abstract

This study investigates the impact of NaF/Al2O3 catalysts on hydrothermal liquefaction (HTL) of cellulose. Three catalysts with varying NaF loadings were synthesized and characterized using XRD, FT-IR, BET, SEM, SEM-EDX, and SEM-EDS. HTL reactions were conducted at 300, 325, and 350 degrees C for 30 min. Elemental, GC-MS, FT-IR and 1H NMR analyses were performed on the liquid products. Results reveal that NaF/Al2O3 catalysts effectively enhance liquid product yield and generate high-energy-value products. NaF-2 and NaF-3 exhibit superior performance in fuel-specific liquid product yield, with increased aliphatics and reduced oxygen compounds. These catalysts display higher carbon content, lower oxygen-to-carbon ratios, and higher heating values, suggesting the production of bio-oils with favorable fuel properties and superior energy values. The findings contribute to understanding catalyst performance in biomass liquefaction, informing efforts to enhance process efficiency and sustainability. Optimum HTL conversion of cellulose occurs with 30% NaF loading.