structure of zeolite, beta, which is used in some hydrocracking catalysts is shown in
Fig. 17 (Baerlocher and McCusker). Beta zeolite is another zeolite with a 12-ring
structure, similar to faujasite; it also has a three-dimensional structure. The diffusion path length is smaller for beta than for faujasite.
Catalyst Manufacturing
Hydrocracking catalysts can be manufactured by a variety of methods. The method
chosen usually represents a balance between manufacturing cost and the degree to
which the desired chemical and physical properties are achieved. Although there is
a relationship between catalyst formulation, preparation procedure, and catalyst
Fig. 15 Y zeolite
Fig. 16 Stabilized Y after
hydrothermal treatment
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