| Mixed a certain percentage of H2S,N2 and H2 togather as sulphide, the single and composite Mo,W,Ni,Co were chosen as hydrotreating catalyst modle, the kinetics of hydrotreating catalyst and its model presulfiding were studied by using method of pulse-fixed-bed microreactor breakthrough under the condition of different reaction temperature and concentration of H2S. The imports and exports concentration of H2S were analysed by titration. The unreacted shrinking reaction core model and the equivalent grain model were used for catalyst particle, the values of parameters were obtained and the model was discussed.The results of intrintic kinetics showed that, under the experiment condition, the higher the temperature and the concentration of H2S were, the greater the conversion rate of the catalyst had. The process of presulfiding could be described by the unreacted shrinking reaction core model,the modle had good applicability, the modle prediction values were approached to the experiment values. Under certain temperature, the overall process was initially in surface reaction controlled regime in the grain and shifted to grain diffusion controlled regime at the middle and last stage. The reaction was first order with respect to H2S concentration. The activation energies of surface reaction was about 10kJ/mol, the order of ks was 10-7-10-5, the solid diffusion energies were higer than activation energies of surface reaction.The results of macro-kinetics showed that, the process of presulfiding could be described by the the equivalent grain model, the overall process was initially in surface reaction and pore diffusion controlled regime in the grain and shifted to grain diffusion and pore diffusion controlled regime at the middle and last stage. The reaction was first order with respect to H2S concentration. The activation energy of surface reaction was 10.5kJ/mol and the solid diffusion energy was 34.9kJ/mol, the solid diffusion energies were higer than activation energies of surface reaction.
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