A regular shape,uniform size Pt nano-polyhedron can be prepared as active ingredient by chemical reduction method,which is supported on a porous Zn Al_2O_4 spinel carrier to prepare new uniform morphology,better dispersion Pt nano-polyhedron/Zn Al_2O_4 catalyst. The physical structure and morphology of the catalyst were characterized by XRD,SEM,TEM etc. and evaluated by a fixed bed dehydrogenation microreactor. The results showed that the new Pt crystal/Zn Al_2O_4 activity was better and the selectivity was...