Confined high dispersion of Ni nanoparticles derived from nickel phyllosilicate structure in silicalite-2 shell for dry reforming of methane with enhanced performance

Novel structure catalyst of Ni@S2-T with Ni nanoparticles highly dispersed in silicalite-2 zeolite (S2) was designed and synthesized via novel two-steps methods, micro-emulsion method followed by solvent-free crystallization route. Due to the unique two-step synthetic process, the confinement effect of the silicalite-2 shell and stronger metal-support interaction caused by the formation of Ni phyllosilicate intermediate in shell, were regarded as the main reasons for the superb catalytic performances of Ni@S2-T for dry reforming of methane (DRM). Compared with Ni-SiO2 by micro-emulsion method, Ni/S2 by impregnation method and Ni@S2-O by direct crystallization, Ni@S2-T catalyst exhibited optimal catalytic activity and stability for DRM. No activity loss was observed during 70 h at high GHSV of 240000 mL g(-1)h(-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.