Behaviors of coke deposition on SAPO-34 catalyst during methanol conversion to light olefins
- 作者：Guozhen Qi ; Zaiku Xie ; Weimin Yang ; Siqing Zhong ; Hongxing Liu ; Chengfang Zhang ; Qingling Chen
- 关键词：MTO ; SAPO-34 ; Coke ; FTIR ; DTA
- 刊名：Fuel Processing Technology
- 出版年：2007
- 期刊代码：36_03783820
- 类别：ce
- 出版时间：May 2007
- 卷：88
- 期：5
- 页码：437-441
- 文件大小：492 K
摘要
The deposition of coke on SAPO-34 during methanol conversion to olefins at temperatures of 623–823 K was observed to be fast initially but moderate in the later stage. Micropores are blocked badly at coke contents of above 4 wt.%. The coke deposition influences olefins selectivity significantly and selectivities of ethylene plus propylene reach maximum at a coke content of about 5.7 wt.%. The coke formation can be attenuated by the presence of water, but the effect of water weakens gradually with the progress of the reaction. A model relating the coke content over SAPO-34 to cumulative amount of methanol fed to the catalysts is proposed and proved the validity to estimate the coke content on SAPO-34 at different reaction conditions. The coke deposited at different reaction temperatures has different compositions.