Petrochemical processing catalysts used

Patents claiming specific catalysts and processes for thek use in each of the two reactions have been assigned to Japan Catalytic (45,47—49), Sohio (50), Toyo Soda (51), Rohm and Haas (52), Sumitomo (53), BASF (54), Mitsubishi Petrochemical (56,57), Celanese (55), and others. The catalysts used for these reactions remain based on bismuth molybdate for the first stage and molybdenum vanadium oxides for the second stage, but improvements in minor component composition and catalyst preparation have resulted in yields that can reach the 85—90% range and lifetimes of several years under optimum conditions. Since plants operate under more productive conditions than those optimum for yield and life, the economically most attractive yields and productive lifetimes maybe somewhat lower. 

Most refinery/petrochemical processes produce ethylene that contains trace amounts of acetylene, which is difficult to remove even with cryogenic distillation. Frequently it is necessary to lower the acetylene concentration from several hundreds ppm to < 10 ppm in order to avoid poisoning catalysts used in subsequent ethylene consuming processes, such as polymeri2ation to polyethylene. This can be accompHshed with catalytic hydrogenation according to the equation. 

CP [Continuous polymerization] A continuous process for making high-density polyethylene, based on the Ziegler process but using a much more active catalyst so that de-ashing (catalyst removal) is not required. Developed by Mitsui Petrochemical Industries and upgraded into its CX process, which was first licensed in 1976. 

Zn and used in the metallurgy of this metal. Pure Mo finds applications also as a catalyst in several petrochemical processes. 

Helene Olivier at the French Petroleum Institute (IFP) at Rueil-Malmaison, near Paris, has developed a butene dimerization process that uses an ionic liquid as a catalyst support (Chauvin et al., 1996). The process offers economic benefits over an existing IFP butene dimerization process widely used in the petrochemical industry. 

These starting values are used as initial guesses for fitting the model to industrial data and the preexponential factors are changed to obtain the best fit. This is done because the kinetic parameters depend upon the specific characteristics of the catalyst and of the gas oil feedstock. This complexity is caused by the inherent difficulties with accurate modeling of petroleum refining processes in contradistinction to petrochemical processes. These difficulties will be discussed in more details later. They are clearly related to our use of pseudocomponents. But this is the only realistic approach available to-date for such complex mixtures. 

Petrochemical processes require smaller reactors than used in refineries. Chemical reactors are sized in the 50 to 250 cu.ft. range. Orders for replacement catalyst usually range from 10,000 to 50,000 lbs, but there are many different process applications. Catalyst quality is becoming more important than in recent years as many industries attempt to reduce the cost of nonconformance and improve the quality of manufactured goods. 

Gallium loaded ZSM-5 is the catalyst used in the Cyclar process (UOP/BP) whereby LPG (largely propane and butane) is converted to high-octane fuels and benzene/toluene/xylene (BTX) as petrochemicals. 

ZSM-5 (Al-MFI) is used as a catalyst in petroleum refining, in the production of synthetic fuels, and in other petrochemical processes, whereas TS-1 (Ti-MFI) is applied as a catalyst in fine chemical processes. The orthorhombic MFI structure exhibits 12 crystallographically unique tetrahedral sites. Calculations have been carried out on substitution preferences using classical as well as quantum models. " In most studies 12 simulations were conducted, and in each run, one or more crystallographically equivalent sites of the subsequently crystallographically unique tetrahedral sites were substituted. Energy minimization and molecular dynamics techniques were employed to calculate... 

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