Issue 5, 2020

Enhancing the matching of acid/metal balance by engineering an extra Si–Al framework outside the Pd/HBeta catalyst towards benzene hydroalkylation

Abstract

The one-step hydroalkylation of benzene to cyclohexylbenzene (CHB) needs to occur on bifunctional metal/zeolite catalysts, and introducing more acid sites to match the metal sites plays a key role in improving the matching of acid/metal sites toward the requirements of benzene hydroalkylation. Herein, we designed and constructed a Si–Al framework coating with extra acid sites outside the surface of the Pd/HBeta catalyst and obtained a zeolite-encaged Pd NP structure (Pd@HBeta). Notably, the Pd@HBeta catalysts achieved excellent catalytic performance with 44.0% CHB selectivity at about 85.0% benzene conversion, which is much higher than that of the Pd/HBeta catalyst with a CHB selectivity of 25.1% at the same benzene conversion. The remarkable increment of CHB selectivity of Pd@HBeta is mainly attributed to the extra acid sites provided by the coated Si–Al framework as well as the increase of the B/L ratio. Moreover, the adsorption capacity of benzene and cyclohexene is greatly improved after introducing extra acid sites by coating the Si–Al framework, which is beneficial for both hydrogenation and alkylation. Further DFT calculations reveal that C6H10 can easily desorb from Pd NPs and migrate to the acidic channel of HBeta in the Pd@HBeta catalyst than that in Pd/HBeta. Our work presents an elegant example of catalytic hydroalkylation selectivity regulation by coating an extra Si–Al framework to enhance the matching of acid/metal balance.

Graphical abstract: Enhancing the matching of acid/metal balance by engineering an extra Si–Al framework outside the Pd/HBeta catalyst towards benzene hydroalkylation

Supplementary files

Article information

Article type
Paper
Submitted
02 Dec 2019
Accepted
23 Jan 2020
First published
25 Jan 2020

Catal. Sci. Technol., 2020,10, 1467-1476

Enhancing the matching of acid/metal balance by engineering an extra Si–Al framework outside the Pd/HBeta catalyst towards benzene hydroalkylation

Z. Li, X. Fu, C. Gao, J. Huang, B. Li, Y. Yang, J. Gao, Y. Shen, Z. Peng, J. Yang and Z. Liu, Catal. Sci. Technol., 2020, 10, 1467 DOI: 10.1039/C9CY02438G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements