Page 107 - Fluid Catalytic Cracking Handbook

CHAPTER 3

FCC Catalysts

The introduction of zeolite in commercial FCC catalysts in the early
1960s was one of the most significant advances in the history of cat
cracking. Zeolite catalysts provided a greater profit with little capital
investment. Simply stated, zeolite catalysts were and still are the
biggest bargain of all time for the refiner. Improvements in catalyst
technology have continued, enabling refiners to meet the demands of
their market with minimum capital investment.
Compared to amorphous silica-alumina catalysts, the zeolite catalysts
are more active and more selective. The higher activity and selectivity
translate to more profitable liquid product yields and additional crack-
ing capacity. To take full advantage of the zeolite catalyst, refiners
have revamped older units to crack more of the heavier, lower-
value feedstocks.
A complete discussion of FCC catalysts would fill another book.
This chapter provides enough information to select the proper catalyst
and to troubleshoot the unit's operation. The key topics discussed are:

• Catalyst Components
• Catalyst Manufacturing Techniques
• Fresh Catalyst Properties
• Equilibrium Catalyst Analysis
• Catalyst Management
• Catalyst Evaluation
• Additives

CATALYST COMPONENTS

FCC catalysts are in the form of fine powders with an average
particle size in the range of 75 microns. A modern cat cracking catalyst
has four major components:
• Zeolite
• Matrix

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