Reduced-crude cracking catalyst

Faced with the need of obtaining more transportation fuels from a barrel of crude, Ashland developed the Reduced Crude Conversion Process (RCC ). To support this development, a residuum or reduced crude cracking catalyst was developed and over 1,000 tons were produced and employed in commercial operation. The catalyst possessed a large pore volume, dual pore structure, an Ultrastable Y zeolite with an acidic matrix equal in acidity to the acidity of the zeolite, and was partially treated with rare earth to enhance cracking activity and to resist vanadium poisoning. 

Hettinger Jr, W. P. Development of a Reduced Crude Cracking Catalyst. Chapter 19 in ACS Symposium Series 375, Edited by M. L. Occelli. Washington, DC ACS, 1988. 

What about the future Like many other industries, catalyst manufacturers are dependent on refinery requirements and crude oil availability. Although crude oil supplies may become limited and catalyst usage reduced, rare earth usage in cracking catalyst may be unaffected. This is because crudes that are likely to be processed are expected to be more difficult to crack requiring higher stability and activity and thus more rare earth exchanged zeolite pef unit of catalyst. 

Although the deleterious effects of metals such as V, Cu, Ni and Fe have been known for well over forty years (1-19), the study of metal resistant fluidized cracking catalysts (FCC) became an area of intense research in industrial and academic laboratories only in the early seventies when the Arab Oil embargo induced nearly a four-fold increase in crude prices and greatly reduced overseas crude availability (2). 

Nickel and vanadium are contained within the crude oil as their respective porphyrins and napthenates (2). As these large molecules are cracked, the metals are deposited on the catalyst. Nickel which possesses a high intrinsic dehydrogenation and hydrogenolysis activity drastically increases the production of coke and dry gas (particularly H2) at the expense of gasoline. Vanadium on the other hand interacts with the zeolitic component of a cracking catalyst and leads to destruction of its crystallinity. This results in reduced activity as well as an increase in non-selective amorphous silica-alumina type cracking. Supported vanadium also has an intrinsic... 

Mobil immediately incorporated zeolites into their moving-bed bead catalysts and in their fluid-bed cracking catalyst formulations. The superiority of these catalysts assured their quick acceptance, and a large increase in profitability. This success attracted imitators and lawsuits. In 1973, the Court indicated that these catalyst had resulted in enormous savings in crude oil, reduced capital plant investment and refining operating costs and had saved the industry more than two billion dollars in the U.S. alone (80). 

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