High stable PtZnLa/Beta catalyst with low Pt loading for propane dehydrogenation

A high stable and active Pt-Zn-La/Beta catalyst with 0.1 wt% Pt loading was studied for catalyzing propane dehydrogenation (PDH) in this work, which is constructed by anchoring La and Zn species onto silanol nests of Beta zeolite at first and then loading Pt on the resultant material after calcination. It is found that the Beta zeolite with the Si/Al ratio of 9.75 is more appropriate than the one with higher Si/Al ratio to be used as the support after the dealumination. And that anchoring La and Zn species prior to Pt onto the silanol nests are quite important. In Pt0.1Zn0.4La0.4/Beta catalyst, La significantly dispersed and stabilized Pt1Zn1 ensembles on the zeolite surface while Zn isolated the Pt atoms and therefore the catalyst is much active, highly selective and catalytic stable. With this catalytic structure, the catalyst provided a high initial propylene formation rate of 113.8 mol(C3H6)<middle dot>g(Pt)(-1)<middle dot>h(-1) with extremely low deactivation constant of 0.0149 h(-1) and a high propylene selectivity of 98 % at 600 degrees C. Graphical abstract