Weisz-Prater number (NW-P) is often applied to assess the internal diffusion effect in heterogeneous catalytic reactions. However, the traditional calculation method with excessive empirical reference values affects the accuracy remarkably. A series of Pt/HPMo/SBA-15 catalysts with the pore size as a single variable were prepared to calculate the NW-P with a developed model combining the diffusion-reaction kinetic method. Utilizing dimensionless variables, internal effectiveness factor (η) and Thiele modulus (Φ_n), and the apparent activities over catalysts with different diffusion capacity, NW-P is obtained with improved accuracy. For the diffusion effect on the hydrotreatment of n-C16, according to the more precise NW-P, the pore size should be not less than 10 nm to avoid the step-limitation of internal diffusion in the premise of adequate acid sites. Using the novel method, a conclusion is drawn that the formation of m-i-C16 is more susceptible to internal diffusion than the consumption of n-C16.

Novel structure catalyst with Ni nanoparticles highly dispersed in silicalite-2 zeolite (S2) was designed and synthesized via a micro-emulsion method followed by solvent-free crystallization route for dry reforming of methane (DRM). Compared with Ni-SiO2 catalyst without crystallization step, Ni/S2 by impregnation method and Ni@S2 prepared by directly crystallization (Ni@S2-O), the Ni@S2-two steps (Ni@S2-T) catalyst exhibited optimal catalytic activity and stability. No activity loss was observed during 70 h at high GHSV of 240000 mL g-1h-1. Meanwhile, Over spent Ni@S2-T catalyst, hardly any coke was found after the prolonged test, which indicated the remarkable anti-coking ability of Ni@S2-T. Thanks to the unique two-step synthetic processes, the confinement effect of the silicalite-2 shell and stronger metal-support interaction causing by the formation of Ni phyllosilicate were regarded as the main reasons for superb catalytic performances.