Improvement of SAPO-34 performance in MTO reaction by utilizing mixed-template catalyst synthesis method

•SAPO-34 was synthesized using TEAOH and morpholine by single/mixed-template methods.•Physiochemical properties of the catalysts were analyzed by XRD, BET, TPD and SEM.•The effects of the template type on SAPO-34 Structure were investigated.•The catalysts were employed for selective conversion of methanol to light olefins.•The products distributions and catalysts life times were compared to each other.

In the present study, the silicoaluminophosphate (SAPO-34) molecular sieves were synthesized by one of tetraethyl ammonium hydroxide (TEAOH) or morpholine structure-directing agents (SDAs) as the single-template and their mixture as the mixed-template methods. The effects of different types and combinations of templates on the structure and morphology of SAPO-34 molecular sieves were investigated by XRD, SEM and BET techniques. The catalytic performance of the synthesized SAPO-34's were investigated in a fixed-bed reactor for methanol to olefin (MTO) reaction. In comparison to single-template SAPO's, mixed-template catalyst possessed larger surface area, smaller particle size and exhibited higher selectivity to light olefins (C2=–C4=) and longer lifetime.