Deactivation during 1-Hexene Isomerization over Zeolite Y and ZSM5 Catalysts under Supercritical Conditions
Deactivation during 1-Hexene Isomerization over Zeolite Y and ZSM5 Catalysts under Supercritical Conditions
复制标题
超临界条件下 Y 型沸石和 ZSM5 催化剂上 1-己烯异构化过程中的失活
DOI：
10.1021/ie101876f
复制
发表时间：
2011
影响因子：
4.2
通讯作者：
Hassan F
中科院分区：
文献类型：
--
作者：
Hassan F
研究了亚临界和超临界条件下 1-己烯异构化过程中 Y 沸石和 ZSM5 沸石中结焦引起的催化失活。研究了两种沸石中不同温度和压力（分别为 220 至 250 °C 和 10 至 70 bar）对转化率和焦炭沉积的影响。比较了新鲜催化剂和焦化催化剂的热重分析（TGA）数据、漫反射红外傅里叶变换光谱（DRIFTS）和氮吸附等温线。在 Y 型沸石中，观察到转化率呈指数衰减，在 235 °C 和 40 bar 的超临界条件下，失活速率比 235 °C 和 10 bar 的亚临界条件更慢。据认为，Y 沸石中直径为 7.4 Å 的微孔可以容纳焦炭分子，从而导致观察到的失活；然而，在 ZSM5 中，直径 5.3-5.6 Å 的微孔太小，无法容纳焦炭分子，因此焦炭沉积在氧化铝粘合剂中孔内的沸石晶体外部。虽然Y沸石失活，而ZSM5没有失活，但超临界流体反应环境的使用使得在235℃、40bar下的转化率比Y沸石Y沸石保持在42%，高于相同条件下ZSM5催化剂34%的转化率。与 ZSM5 的性能相比，使用超临界流体操作可以部分缓解 Y 型沸石所观察到的显着结焦效应，并提高其用于该反应的可行性。
Catalytic deactivation caused by coking was studied in zeolite Y and ZSM5 during 1-hexene isomerization under subcritical and supercritical conditions. The effects of varying temperature and pressure, from 220 to 250 °C and from 10 to 70 bar, respectively, on conversion and coke deposition were studied in both zeolites. Thermogravimetric analysis (TGA) data, diffuse reflectance infrared Fourier transform spectra (DRIFTS), and nitrogen sorption isotherms for fresh and coked catalysts were compared. In zeolite Y an exponential decay in conversion was observed with the rate of deactivation being slower at supercritical conditions at 235 °C and 40 bar than subcritical conditions at 235 °C and 10 bar. It is thought that in zeolite Y the micropores with diameter 7.4 Å could accommodate coke molecules leading to the observed deactivation; however, in ZSM5 the micropores of 5.3–5.6 Å diameter were too small to accommodate coke molecules, and thus coke was deposited outside the zeolite crystals within the mesopores of the alumina binder. Although zeolite Y deactivated, while ZSM5 did not, the use of a supercritical fluid reaction environment enabled the conversion at 235 °C, 40 bar to be maintained at 42% over zeolite Y, which was higher than the conversion of 34% over ZSM5 catalyst under the same conditions. Operating with supercritical fluid led to the partial alleviation of the significant coking effects observed with zeolite Y and improved its viability for use in this reaction compared with the performance of ZSM5.
登录
查看更多内容
影响因子：
4.7
作者：
Peter I. Chigada;Jiawei Wang;B. Al-Duri;J. Wood;S. Rigby
通讯作者：
Peter I. Chigada;Jiawei Wang;B. Al-Duri;J. Wood;S. Rigby
影响因子：
4.2
作者：
Jiawei Wang;Faiza Hassan;Peter I. Chigada;S. Rigby;B. Al-Duri;J. Wood
通讯作者：
Jiawei Wang;Faiza Hassan;Peter I. Chigada;S. Rigby;B. Al-Duri;J. Wood
以乙苯歧化为例的超临界条件下除焦的失活动力学和建模
影响因子：
2.1
作者：
F. Niu;G. Kolb;H. Hofmann
通讯作者：
H. Hofmann
一种温和有效的多相催化剂活性重新激活或维持方法
影响因子：
--
作者：
H. Tiltscher;H. Wolf;J. Schelchshorn
通讯作者：
J. Schelchshorn
锗改性 H-ZSM5 沸石上的丙烷转化
影响因子：
2.8
作者：
C. Salguero;Y. L. Lam;M. Schmal
通讯作者：
M. Schmal