Abstract: Using concentrated nitric acid, peroxyacetic acid, hypochlorous acid as oxidant and silica-gel with different pore structures as adsorbent, the silica gel loaded with acid oxidant was prepared by mixing and characterized by IR and N2 adsorption-desorption. The effects of silica gel pore structure on desulfurization of model diesel with 1 000 μg/g of 4,6-dimethyldibenzothiophene（4,6-DMDBT）by strong oxidative acids were investigated. The results show that the pore structure of silica gel hardly relates to the desulfurization efficiency for peroxyacetic acid. However, the pore size of the silica gel has great influence on the S removal for hypochlorous acid with relative larger molecular size. Both pore diameter and inner specific surface area affect the desulfurization efficiency significantly for concentrated nitric acid. No relations of oxidative products and silica gel pore structure are observed.

Key words: diesel desulfurization, oxidation-adsorption, silica gel pore structure, strong oxidative acid