Characterization and optimization of SAPO-34 catalysts synthesized by mixed templates in MTO reaction

Document Type: Full article

Authors

Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, Iran

Abstract

"> The effects of templating on the catalytic performance of SAPO-34 catalyst have been investigated in conversion of methanol to olefins. SAPO-34 catalysts were synthesized using a different combination of morphine, tetraethyl ammonium hydroxide (TEAOH) and triethylamine (TEA) as structure-directing agents during synthesis of gel with nominal composition as 1Al2O3:1P2O5:0.4SiO2:2yTEAOH:2xTEA:2(1-(x+y))morpholine:70H2O. The different SAPO-34 samples were characterized by XRD, SEM, FTIR, BET, EDX and TPD techniques. Increasing TEAOH in synthesis gel led to decreasing mean crystal size. The catalytic performance of the synthesized catalysts was tested in MTO reaction at 410C and a feed WHSV of 6.5 1/h. The catalyst synthesized by combination of tri-templates exhibited highest light olefins yield in 100% methanol conversion. The optimum values (X=0.17, Y=0.34) were obtained by central composite design and response surface contour plots.

Keywords


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