Acid properties of solid acid from petroleum coke by chemical activation and sulfonation

Abstract

Abstract A novel solid acid was prepared from petroleum coke by KOH chemical activation and concentrated H 2 SO 4 sulfonation. The solid acid was characterized by XRD, FT-IR and solid-state NMR. The characterization results show that the chemical activation and sulfonation lead to three functional Bronsted acid sites: –OH, –COOH and –SO 3 H on the solid acid. The probe molecules experimental reveal that the acid strength of the solid acid is stronger than that of SO 4 2− /ZrO 2 , but slightly weaker than that of 100% H 2 SO 4 . The catalytic performance was evaluated by the esterification of oleic acid with methanol. The results indicate that this solid acid catalyst is very active, corresponding to high conversion (72%) of esterification reaction. In addition, the spent solid acid can be recovered by simple regeneration process.