Shima Masoumi - Department of Chemical Engineering, Tarbiat Modares University, Tehran, Iran
mehdi sedighi
jafar towfighi
ali mohamadalizadeh

Silicoaluminophosphate, SAPO-34, is known as promising molecular sieve, which is widely used in catalysis, separation processes, and are being developed for new applications, especially in the methanol-to-olefin (MTO) process. To investigate the effects of different templates on the SAPO-34 structure, SAPO-34 catalysts were synthesized using a different combinations of morpholine, tetraethyl ammonium hydroxide (TEAOH) and tetraethyl amine as structure-directing agents during synthesis of gel with nominal composition as 1Al2O3: 1P2O5: 0.4SiO2: 2y TEAOH: 2x TEA: 2(1-(x+y)) morpholine: 70H2O. The sources of Al, Si, and P are aluminum isopropoxide, silica gel, and phosphoric acid, respectively.The different SAPO-34 samples were characterized by XRD and SEM and FTIR techniques. XRD patterns revealed the significant effect of gel composition on the crystallinity. According to the XRD and SEM, highest crystallinity and smallest crystal size was formed when TEAOH-MOR-TEA were used as templates. Furthermore, this sample exhibited the highest content of hydroxyl groups

SAPO-34, Synthesis, Structure-directing agent, Crystallinity