Practical Application of Hierarchical Beta Zeolite in a Vacuum Gas Oil Hydrocracking Catalyst

Abstract

A hierarchical Beta zeolite has been successfully mass-prepared hydrothermally and dynamically in a pilot-scale autoclave by an economical and simple process with low-cost raw materials. The characterization results indicated that the pilotscale hierarchical Beta zeolite has the same textural, structural, and acidic properties like the bench-scale sample. Moreover, the catalyst composed of the pilot-scale hierarchical H-Beta zeolite showed higher activity and selectivity to the middle distillate than that containing microporous Beta zeolite in catalytic hydrocracking of vacuum gas oil (VGO) evaluated by an industrial pilot installation in running of 3000 h, due to the increased accessibility and the reduction of diffusion constraint of large molecules to acid sites in the Beta zeolite framework.

Crystallization of zeolite Beta in the presence of an anionic surfactant AESA

“…Zeolites are a series of microporous crystalline aluminosilicates, which are widely utilized for applications including adsorption, catalysis and ion exchange. [1][2][3][4][5] In particular, zeolites are the most important solid catalysts in the petrochemical industry due to their well-defined micropores of molecular dimensions that host the active sites. 6 Among them, zeolite Beta is one of the widely applied and extensively studied zeolites, which has an open-framework structure of three dimensional 12-membered ring channels with a diameter of 0.67 nm.…”

“…[26][27][28][29] Cationic surfactants, such as cetyltrimethylammonium bromide (CTAB), have been applied in the synthesis of hierarchical zeolites with a high external surface area. 2,30 In a typical solution-mediated process, CTA + ions can be enriched at the liquid-solid interface through a strong electrostatic force between the polar head groups of CTA + and the negative charged microcrystal surface, compensating partially the negative charge from the newly formed microcrystal surfaces, which further hinders the growth of zeolitic microcrystals and increases the external surface area. 30 However, the application of negatively charged organic molecules in zeolite crystallization is seldom reported.…”