Nitrogen containing SAPO-34 molecular sieves were prepared by a secondary technique with a starting material of SAPO-34 treatment at elevated temperature by ammonia in this study. Comparing with precursor, the obtaine...Nitrogen containing SAPO-34 molecular sieves were prepared by a secondary technique with a starting material of SAPO-34 treatment at elevated temperature by ammonia in this study. Comparing with precursor, the obtained samples still kept high crystallinity and high specific surface area after treated at high temperature for different times detected by XRD and BET measurements. The catalytic performance of nitridized samples for MTO(methanol make olefins) was investigated. It was found that olefins selectivity was increased on the SAPO-34 molecular sieve treated by ammonia, ethylene selectivity increased from 11.6% to 39.7%. Nitridation changed the acidity of SAPO-34 molecular sieve, which responsible for light olefins.展开更多
文摘Nitrogen containing SAPO-34 molecular sieves were prepared by a secondary technique with a starting material of SAPO-34 treatment at elevated temperature by ammonia in this study. Comparing with precursor, the obtained samples still kept high crystallinity and high specific surface area after treated at high temperature for different times detected by XRD and BET measurements. The catalytic performance of nitridized samples for MTO(methanol make olefins) was investigated. It was found that olefins selectivity was increased on the SAPO-34 molecular sieve treated by ammonia, ethylene selectivity increased from 11.6% to 39.7%. Nitridation changed the acidity of SAPO-34 molecular sieve, which responsible for light olefins.
