Kinetics of desulfurization by electrochemical oxidation in an emulsifying electrolyte

Abstract

ABSTRACTDiesel with S content 624.4 µg/g was directly used, and a constant current of 500 mA was proposed in this work. Emulsification as an enhancement method was used to enhance the interphase mass transfer. After emulsifying electrochemical oxidation–extraction, the sulfur content of diesel decreased to 8.1 µg/g and the desulfurization efficiency reached 98.71 %. On comparingwith the non-emulsifying electrochemical oxidation–extraction, it has a highly efficient deep desulfurization.The analysis also found that the effect of emulsion and non-emulsion extraction desulfurization process on electrochemical oxidation has great difference under the same operating conditions, and parameters such as the order, reaction rate and activation energy of the two kinds of oxidation desulfurization reaction were studied. The results showed the oxidative desulfurization reaction is the first reaction. When the temperature reached T2, the oxidation rate constant of the emulsion/non-emulsion system was 0.0199 min−1 and 0.0179 min−1, respectively. When the temperature reached T1, the oxidation rate constant of the emulsion/non-emulsion system was 0.0375 min−1 and 0.0346 min−1, respectively. According to Arrhenius' law, the apparent activation energy of sulfur compounds in the raw oil is Ea (emulsion) = 6.9783 kJ/mol and Ea (non-emulsion) = 9.1826 kJ/mol, respectively.