Preparation of a Sulfonated Porous Carbon Catalyst with High Specific Surface Area

Abstract

A sulfonated (SO3H-bearing) carbon catalyst with mesoporous structure and high specific surface area is successfully prepared by impregnating the cellulosic precursor (wood powder) with ZnCl2 prior to activation and sulfonation. The specific surface area of the porous carbon catalyst thus prepared is also found to increase with carbonization temperature to a maximum of 1,560 m2 g−1 at ca. 773 K. Structural analyses reveal that the porous carbon catalysts carbonized at temperatures higher than 723 K contain high densities of micro- and mesopores. The porous carbon catalyst exhibits high catalytic performance for the esterification of acetic acid (343 K), the activity for which is dependent only on the acid density. The porous carbon catalyst also exhibits high catalytic activity for the benzylation of toluene, whereas non-porous sulfonated carbon has very limited activity for this reaction. The activity for the benzylation of toluene is dependent on both the specific surface area and the acid density of the sulfonated porous carbon catalyst.