Alkylation of isobutane with butenes using OSDA-free zeolite beta

The acid-catalyzed alkylation of isobutane with butenes is an important contributor to the production of high-quality gasoline. Recent advances in this field focus on the development of solid acid catalysts to substitute current liquid-based alternatives. La-exchanged faujasite (La-HY) has been implemented industrially due to its excellent activity and selectivity, but remains prone to deactivation. In this work, Beta zeolites from seeded syntheses (without organic structure directing agents, OSDAs) were investigated as an industrially viable alternative with increased catalyst productivity. First, their stability in alkylation was benchmarked against that of OSDA-based Beta zeolites in batchwise, deactivating operational conditions. Herein, the OSDA-free Beta significantly outperformed OSDA-based zeolites. The time-on-stream behavior of OSDA-free Beta was evaluated in a CSTR setup. In optimal conditions, a productivity above 30 g(prod)/g(cat) and selectivity above 85% to C-8 were obtained. Moreover, OSDA-free Beta outperformed the industrial benchmark La-HY. After reaction, this catalyst can be regenerated three times without loss of activity, preferably via a regeneration under hydrogen. (C) 2022 Elsevier Inc. All rights reserved.

Automated summary

This study investigates the use of OSDA-free Beta zeolites as an alternative catalyst for the acid-catalyzed alkylation of isobutane with butenes. The OSDA-free Beta zeolites show excellent catalytic performance and stability, outperforming OSDA-based zeolites and the industrial benchmark La-HY.