Fluid Cat Cracking

Fluid cat cracking required identifying stable operating regimes for beds of fine catalyst at high gas flow rates. Highly efficient cyclone and electrostatic systems had to be developed for catalyst recovery. Finally, the principles of pressure... 

Fluid bed processes have been subject to many problems and uncertainties in development and scale up from bench-scale reactors. The fluidization behavior of each process seems different and very often does not meet expectations based on experience with earlier plants. With hindsight fluid cat cracking seems to be an ideal system from the point of view of easy operation and straightforward scale up. 

Hsich, C. R. and English, A. Ar., Two Sampling Techniques Accurately livaluate Fluid-Cat-Cracking Products, Oil Gas Journal, June 23, 1986. pp, ts-43. 

Andersson, S-I. Otterstedt, 3-E. Paper presented at Katalistiks 8th Annual Fluid Cat Cracking Symposium, Budapest, Hungary, 3une, 1987. Speight, 3. G. The Desulfurization of Heavy Oils and Residue Marcel Dekker New York, 1981. 

Aitken, E. 3. Baron, K. McArthur, D. P. Paper presented at Katalistiks 6th Annual Fluid Cat Cracking Symposium, Munic, May, 1986. 

Cabrera, C. A., Helmer, C. L., and Davis, J. P., Paper 14, Katalistiks 8th Annual Fluid Cat Cracking Symposium, June 1-4,... 

Today much of the propylene used in the world is produced by the catalytic hydrocarbon cracking in fluid cat-cracking and similar operations . 

Fluid catalytic cracking, fluid cat-cracking or FCC, is a common oil refinery process. The duty of an FCC unit is to take a heavy low value gas oil or fuel oil and convert this to higher valued liquid products, particularly gasoline blend-stock. The process also produces diesel fuel blend-stock and a gas by-product stream. The gaseous by-products are rich in olefins and in particular propylene and isobutene. Ethylene is a minor component. 

The coke formation leads to catalyst fouling. This is solved in the UOP Process by continuously removing a portion of the catalyst and passing this to a separate regenerator. After regeneration by combustion of the coke in air, the catalyst is sent back to the main reactor. In concept this is similar to fluid-cat cracking of refinery stocks. The process layout is illustrated in the Figure 11.7. 

Even more efficient processes were introduced later in the war. Mobil developed a moving bed process called Thermofor Catalytic Cracking and a new synthetic amorphous cracking catalyst (Ref. 1), while Exxon led a group of companies in developing fluid cat cracking. These processes provided the Armed Forces with plentiful supplies of 100 octane aviation fuel in the latter stages of World War II and they were a decisive element in the final Allied victory in Europe. 

W. Groenendaal, What is new for Fluid Cat Cracking - Outlook in Western Europe - Katalistiks 7th annual symposium, 1986. 

Chemical fluidized-bed reactors can have diameters of up to 10 m. Their scale-up is associated with major risks (erosion of reactor walls and especially cooling tubes, bubble formation, solids entrainment, formation of flnes), so that today the main application is syntheses with large heats of reaction (e.g., acrylonitrile, maleic anhydride, fluid cat cracking) and fluidized combustion. 

Olsen and Sterba, Effect of Reactor Temperature. . . Fluid Cat. Cracking, Chem, Eng. Progr., November, 1949, p. 692. 

Gohr, E. J., Advances in Fluid Cat. Cracking, Proc. Fourth World Pet. Congr., sec. Ill, Rome, 1955. 

In the second application, we discuss the use of surface charging concepts and zeta potential measurements to optimize the attrition resistance of fluid cat cracking (FCC) catalyst composite particles. The FCC particles consist of micron size zeolite particles held together by submicron sol particles to form 50-70p composites. In this study, we start with a suite of USY zeohtes of variable bulk Si-Al ratios and first determine their relative surface compositions using isoelectric points (lEP). We estabhshed an excellent... 

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