Intrinsic Kinetics of Hydrorefining Catalyst in Ex-Situ Presulfurization

Jianwei Zhang, Jian Wang, Kai Wu

Provincial Key Laboratory of Oil and Gas Chemical Technology, College of Chemistry and Chemical Engineering, Northeast Petroleum University, Daqing, China.
Wax Workshop of Oil Refinery Plant of Daqing Petrochemical Company, Daqing, China.

DOI: 10.4236/wjet.2014.22012                

Abstract

The intrinsic kinetics of hydrorefining catalyst in ex-situ presulfurization was investigated using a fixed-bed penetrating method. A mathematical model was built to express the intrinsic kinetics of presulfurization using an unreacted shrinking core model for catalyst grains and one-dimension unhomogeneous model for beds, and then the significance of the new model was tested. Results show that the presulfurization with hydrorefining catalyst was a nonstationary process, as the reaction rate changed with time, and this first-order reaction displayed high activation energy. In this dynamic mathematical model, a correction coefficient f0 was introduced into the common power-function-formed rate equation, which indicated the effects of solid diffusion on reaction. The model with high significance was able to improve the presulfurization rate and the raw material utilization ratio, thus providing theoretical guidance for achieving high presulfurization effects.

Keywords

Hydrogenation Catalyst, Presulfurization, Intrinsic Kinetics, Unreacted Shrinking Core Model

Conflicts of Interest

The authors declare no conflicts of interest.

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