Enhanced Pt dispersion and catalytic properties of NaCl-promoted Pt/MFI zeolite catalysts for propane dehydrogenation

A simple and scalable method is presented for preparing propane dehydrogenation catalysts with superior catalytic properties. Pt distribution is significantly improved when the platinum precursor and a large amount of NaCl are introduced into the MFI zeolite by impregnation, and after calcining and fixing the active components in the insoluble form, the excess of inert salt is washed with water. NaCl promotes Pt dispersion, prevents sintering during calcination, and effectively suppresses zeolite acidity. Washing after the calcination of Pt-containing catalysts further increases the catalyst activity and stability due to the redispersion of water-soluble chlorinated Pt compounds. High external surface acid site concentrations, Na/Pt atomic ratios of 40-70, calcination temperatures of 400-500 degrees C, washing with water, and the order of component introduction when the excess NaCl and the precursor of Pt are calcined jointly contribute to improved Pt dispersion and catalyst stability.

Automated summary

The introduction of NaCl improves Pt dispersion and catalyst stability, while washing after calcination further enhances catalyst activity through the redispersion of Pt compounds.