Effect of different combination of TEAOH/Morpholine on the catalytic bahaviour of SAPO-34 catalyst in MTO process

SAPO-34 molecular sieves were synthesized under hydrothermal conditions by using TEAOH, morpholine and a mixture of them as structure-directing agents. The properties of the catalysts were characterized using XRD and FT-IR. The results showed that using a mixed template lead to the reduction of particle size. The catalytic performance of the synthesized catalysts was tested in MTO reaction with different time-on-stream. All the samples showed highactivity and selectivity to light olefins at the initial stage of the reaction. The maximum yield of ethylene, propylene and butene was determined 12.57, 13.45 and 2.21 wt.%, respectively. The catalyst produced by the TEAOH/morpholine ratio of 1:1 exhibited the longest catalyst lifetime.

Keywords:

MTO , SAPO-34 , Acidity , Crystallite size , Stability