Effect of calcination temperature and composition on the spray-dried microencapsulated nanostructured SAPO-34 with kaolin for methanol conversion to ethylene and propylene in fluidized bed reactor

Abstract

The reported research can be related to the investigation of MTO catalysts prepared via spray drying method and the corresponding catalytic evaluation with the aim of improving SAPO-34 catalyst strength and reduce its abrasion. Slurry composition and calcination temperature effect on the production of fluidizable microencapsulated catalysts was taken into account. Characterization of the spray dried samples was investigated by NH3-TPD, BET-BJH, XRD, EDX, FESEM, FTIR and TGA analysis. Intensity reduction of the reflections at 2θ = 12.5 and 24.7° and disappearing from the XRD pattern at calcination temperatures higher than 550 °C proves the conversion of kaolinite phase to metakaolinite. The results demonstrate new Brønsted acid site for the spray dried sample compared to the results of bare SAPO-34. Thus, the optimized values for the composition of the spray drying slurry and the corresponding final calcination temperature were reported for the fluidizable MTO catalyst. KA-SAPO (S/K = 0.8 Al = 11 T = 550) catalyst was introduced as an acceptable catalyst in MTO process having life time of 900 min in fluidized bed reactor.