...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Catalysis science & technology >Elucidating the olefin formation mechanism in the methanol to olefin reaction over AlPO-18 and SAPO-18
【24h】

Elucidating the olefin formation mechanism in the methanol to olefin reaction over AlPO-18 and SAPO-18

机译：阐明甲醇中烯醇的烯烃形成机理在ALPO-18和SAPO-18上烯烃反应

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The mechanism of the methanol to olefin (MTO) reaction over AlPO-18 (without Bronsted acid sites) and two SAPO-18 (with different Bronsted acid site densities) catalysts has been investigated. The Bronsted acid site density of AlPO-18 and SAPO-18 catalysts was determined by ~1H MAS NMR spectroscopy. Methanol conversion over the catalysts showed that the catalytic activity of the catalysts was strongly influenced by their Bronsted acid site density. Using ~(13)C magic angle spinning (MAS) NMR, we directly observed the pentamethylcyclopentenyl cation (pentaMCP~+) over SAPO-18 under real MTO reaction conditions, but no carbenium ion was detected over AlPO-18. Furthermore, analysis of confined organics by ~(13)C MAS NMR and GC-MS clearly demonstrated that higher Bronsted acid site density improved the formation and accumulation of some important and reactive hydrocarbon pool species, such as pentaMCP~+ and polymethylbenzenes. With the aid of the ~(12)C/~(13)C-methanol switch technique, the detailed olefin formation mechanism was elucidated. During the MTO reaction, light olefin generation over SAPO-18 mainly followed the aromatic-based hydrocarbon pool mechanism; however, the olefin methylation and cracking mechanism accounted for the production of light olefins over AlPO-18.
机译：已经研究了甲醇对ALPO-18（不含Bronsted酸位点）和两个SAPO-18（带有不同Bronsted酸位点密度不同）的甲醇（MTO）反应的机理。 ALPO-18和SAPO-18催化剂的Bronsted Acid位点密度通过〜1H MAS NMR光谱测定。催化剂上的甲醇转化率表明，催化剂的催化活性受其Bronsted Acid位点密度的强烈影响。使用〜（13）C魔法旋转（MAS）NMR，我们直接观察到在实际MTO反应条件下SAPO-18上的五甲基环丙烯基阳离子（pentamcp〜+），但在Alpo-18上未检测到碳纤维离子。此外，〜（13）C MAS NMR和GC-MS对限制有机物的分析清楚地表明，较高的Bronsted Acid位点密度改善了某些重要和反应性的碳氢化合物池的形成和积累，例如pentamcp〜++ polymetymethylbenzenes。借助〜（12）C/〜（13）C-甲醇开关技术，阐明了详细的烯烃形成机制。在MTO反应过程中，SAPO-18上的光烯烃产生主要遵循基于芳香族的烃池机制。然而，烯烃甲基化和开裂机制造成了烯烃在ALPO-18上的产生。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号