Synthesis porous carbon-based solid acid from rice husk for esterification of fatty acids

A porous carbon solid acid was synthesized from biomass rice husk by incompletely carbonization, sodium hydroxide leaching and concentrated H2SO4 sulfonation. The solid acid was characterized by XRD, FT-IR, N-2 adsorption-desorption and solid-state NMR spectroscopy. The characterization results reveal that the carbon solid acid shows ultra high surface area of 1233 m(2)/g and stronger acid strength than that of HZSM-5(Si/Al = 38) zeolite. The catalytic performance was tested by the esterification of oleic acid with methanol. The results indicate that this solid acid catalyst is an excellent catalyst compared with other conventional solid acid. (C) 2015 Elsevier Inc. All rights reserved.