Biomass-Based Sulfonic-Functionalized Carbon Solid Acid for Esterification of Acetic Acid

摘要

Sulfonic-functionalized carbon material derived from the incomplete carbonization of mungbean vermicelli was reported here as a catalyst for esterification of acetic acid. The catalyst with the highest activity (S_(BET) = 18.1 m~2/g and acid site density of 1.53 mmol H~+/g_(cat)) was obtained by carbonization at 573 K and sulfonation at 373 K due to a feasible attachment of more - SO_3H groups to flexible carbon sheets compared to the other synthesized solids. Approximate 64% yield of methyl acetate was achieved over (2:1) molar ratio of methanol to acetic acid with 3 wt.% of catalyst. From the economic outlook, this environmentally benign C-SO_3H catalyst could be a promising candidate for the esterification of high free fatty acid feedstocks reducing the production cost of biodiesel.