An effective method to enhance the stability on-stream of butene aromatization: Post-treatment of ZSM-5 by alkali solution of sodium hydroxide
An effective method to enhance the stability on-stream of butene aromatization: Post-treatment of ZSM-5 by alkali solution of sodium hydroxide
复制标题
DOI：
10.1016/j.apcata.2005.12.023
复制
发表时间：
2006-03-21
影响因子：
5.5
通讯作者：
Xu, LY
中科院分区：
文献类型：
--
作者：
Song, YQ;Zhu, XX;Xu, LY
通过适当浓度的氢氧化钠溶液处理ZSM-5沸石，提高了ZSM-5沸石在丁烯芳构化中的催化稳定性。通过表征孔结构、催化剂的酸度和焦炭量，我们发现ZSM-5的碱处理导致由于优先去除硅物质而形成新的介孔，而固有微孔保持不变。至于酸度，碱处理的ZSM-5沸石上酸位的数量和性质表现出轻微的变化。此外，对ZSM-5沸石进行碱处理仅导致丁烯芳构化过程中焦炭量的少量减少。但由于碱处理，一部分焦炭沉积在新产生的中孔中，并且发现微孔中焦炭的形成减少。这些变化可以抑制丁烯芳构化过程中焦炭沉积物对ZSM-5沸石通道的堵塞。结焦位置的变化是丁烯芳构化过程中反应稳定性有利增强的主要原因。 (c) 2005 Elsevier B.V. 保留所有权利。
The catalytic stability of ZSM-5 zeolite in butene aromatization was improved by the treatment of ZSM-5 zeolite with sodium hydroxide solution of appropriate concentration. By characterizing pore structures, the acidity of the catalyst and the coke amount, we found that alkali-treatment of ZSM-5 led to a formation of new mesopores resulting from a preferential removal of silicon species, while the intrinsic micropores remained unchanged. As for the acidity, the amount and properties of acid sites exhibited a slight change on the alkali-treated ZSM-5 zeolites. In addition, the alkali-treatment to ZSM-5 zeolite led to only a little reduction in the amount of coke during the butene aromatization. But a portion of coke was deposited in the newly created mesopores because of the alkali-treatment and the formation of coke in the micropores was found to be reduced. These changes can suppress the channel blockage of ZSM-5 zeolite by the coke deposits during butene aromatization. The variation of the coking location was the main reason for the favorable enhancement in the reaction stability during butene aromatization. (c) 2005 Elsevier B.V. All rights reserved.