Stability studies of PtSn structured catalysts supported on thin layers of MAl2O4 (M: Mg or Zn) for paraffins dehydrogenation reactions

ADRIANA D. BALLARINI; PATRICIA D. ZGOLICZ; SERGIO R. DE MIGUEL; SONIA A. BOCANEGRA

THE CANADIAN JOURNAL OF CHEMICAL ENGINEERING

JOHN WILEY & SONS INC

Lugar: New York; Año: 2022

0008-4034

In order to determine the catalytic stability, PtSn structured catalysts supported on thin films of MgAl2O4 or ZnAl2O4 deposited on -Al2O3 spheres were studied through five reaction-regeneration cycles in the n-butane dehydrogenation. Bimetallic catalysts show good catalytic stability along the five reaction-regeneration cycles. Among the different synthesized catalysts, the PtSn/Sp-Zn-CN catalyst showed the best catalytic behaviour, showing very good values of yields to butenes and excellent catalytic stability along the cycles, even better than the one of a structured commercial catalyst used industrially for dehydrogenation of paraffins. The characterization results by Temperature Programmed Reduction and X-ray Photoelectron Spectroscopy showed some modifications in the metallic phase of the catalysts after the cycles, mainly in the Sn/Pt surface ratios and in segregation effects in some catalysts.. However, the TEM results are conclusive in the sense that, after the cycles, the bimetallic catalysts maintained a very high proportion of particles with sizes between 1 and 2 nm, and therefore, preserved a high metallic dispersion.