Use of Zeolites in Catalytic Cracking

The use of cracking catalysts containing zeolite increased rapidly following their introduction in 1962, and by 1972 they were being used in at least 90% of the FCC units in the United States. Gasoline prodnction was increased, with a lower role of recycle of the residual heavy oil. Gas oil feed rate could, therefore, be increased. Zeolites were produced with more consistent quality and were relatively more stable, producing less coke during operation tlm synthetic sili-ca/alumina catalysts. 

Some early zeolite catalysts contained X-zeolite, probably because it was 

Catalyst Gasoline Gasoline, octane Octane, residue, reformulated gasoline. 

Zeolite X/Y-zeolite, REY-zeolite REY-zeolite, REUSY-zeolite REUSY-zeolite 

Matrix Kaolin Kaolin Alumina (major), sili-ca/alumina, cerium-pillared clays, acid treated meta kaolin. 

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