Molecular characteristics of sulfur compounds in oxidative desulfurization for heavy fuel oil based on APPI FT-ICR MS analysis

Oxidative desulfurization of model oil and heavy fuel (HFO) was investigated under mild conditions using H2O2 as an oxidant acetonitrile extractant. The influence factors in the oxidation extraction processes were evaluated optimized. molecular characteristics raw feedstock desulfurized oils, corresponding phases systematically analyzed by APPI FT-ICR MS, 1H NMR, etc. results showed that rate dibenzothiophene reached 97.7% after 10 min reaction, while sulfur removal efficiency HFO 30.7% optimized conditions. structures compounds described heteroatom type, carbon number distribution vs unsaturation degree. detected main sulfur-containing are S1, S2, S3, NS, OS, O2S, O2S2, O4S2. Based on MS results, it can be found almost all S1 species have been transformed into sulfone process. Furthermore, O2S1 O4S2 double bond equivalent (DBE) range from 9 to 25 with ≤ 40. NMR α aromatic CH3 combined naphthenic CH-CH2 group accounted for 73.2% phase.