Ultrasonic and Microwave Pretreatment for Hydrothermal Synthesis of NanosizedSAPO-34s and their Catalytic Performance in MTO Reactio

In order to enhance the catalytic performance of SAPO-34 catalyst for the reaction of methanol toolefins (MTO), ultrasonic and microwave-assisted aging method was employed in static hydrothermalmethod to synthesize nano-sized SAPO-34. The effects of the application of this method on thechemical composition, morphology, surface area and total acidity of SAPO-34 were investigated byXRD, FE-SEM, nitrogen adsorption–desorption and NH3-TPD techniques. The catalytic performanceof synthesized SAPO-34 was investigated for MTO reaction in a fixed-bed reactor under the sameoperating conditions (T = 450 °C, P = 1 atm, and WHSV = 4 h−1). Comparing with the SAPO-34synthesized with conventional hydrothermal method, the sample synthesized with simultaneous use ofUS and MW-assisted aging methods possessed larger surface area and small crystal size and exhibitedhigher selectivity to light olefins ( 2 4 )C = - C = and longer lifetime

Keywords:

SAPO-34NanocatalystsMTO ReactionLifetimeLight Olefins