Reforming, petroleum

Styrene is manufactured by alkylating benzene with ethene followed by dehydrogenation, or from petroleum reformate coproduction with propylene oxide. Styrene is used almost exclusively for the manufacture of polymers, of which the most important are polystyrene, ABS plastics and styrene-butadiene rubber. U.S. production 1980 3 megatonnes. 

Research into cluster catalysis has been driven by both intrinsic interest and utilitarian potential. Catalysis involving "very mixed -metal clusters is of particular interest as many established heterogeneously catalyzed processes couple mid and late transition metals (e.g., hydrodesulfurization and petroleum reforming). Attempts to model catalytic transformations arc summarized in Section II.F.I., while the use of "very mixed -metal clusters as homogeneous and heterogeneous catalysis precursors are discussed in Sections I1.F.2. and I1.F.3., respectively. The general area of mixed-metal cluster catalysis has been summarized in excellent reviews by Braunstein and Rose while the tabulated results are intended to be comprehensive in scope, the discussion below focuses on the more recent results. 

Aromex A process for removing aromatic hydrocarbons from petroleum reformate by extrachon with diglycolamine (also called [2-(2-aminoethoxy) ethanol], and DGA). Developed by Howe-Baker Engineers. See also Econamine. 

Aromizing A petroleum reforming process for converting aliphatic to aromatic hydrocarbons. Developed by the Institute Frangais du Petrole. 

PHD A petroleum reforming process operated in Germany from 1940. The catalyst was molybdena on alumina. 

Enciforming [National Chemical reforming] A petroleum reforming process that converts pyrolysis gasoline to mixtures of propane, butane, and aromatic hydrocarbons, thereby obviating the usual hydrogenation and solvent extraction processes. The catalyst is a ZSM-5-type zeolite containing both iron and a platinum metal. Developed by the National Chemical Laboratory, Pune, India, since 1988, but not yet commercialized. 

Formex A process for extracting aromatic hydrocarbons from petroleum reformate, using N-formyl morpholine at 40°C. Developed by SNAM-Progetti. 

HF A predecessor of the DHD petroleum reforming process, operated in Germany in 1939. The catalyst was a mixed Mo03/Zn0/Al203 system. 

Iso-Plus Houdriforming A complex petroleum "reforming process, based on the Houdriforming process. Developed by the Houdry Process and Chemical Company. 

OCTENAR [Octane enhancement by removing aromatics] A process for removing aromatic hydrocarbons from petroleum reformate by extractive distillation with N-formyl mor-phylane. The product can be blended with gasoline to increase its octane number — hence the name. A paraffin mixture is obtained as a side-product. Developed by Krupp Koppers from its MORPHYLANE and MORPHYLEX processes. 

SBK [Sinclair-Baker-Kellogg] A petroleum reforming process which uses a regenerable platinum catalyst. 

Attention will be focussed on three typical chemical reaction schemes. For the first illustration, two parallel competing reactions are considered. For instance, it may sometimes be necessaru to convert into a desired product only one component in a mixture. The dehydrogenation of six-membered cycloparaffins in the presence of five-membered cycloparaffins without affecting the latter is one such example of a selectivity problem in petroleum reforming reactions. In this case, it is desirable for the catalyst to favour a reaction depicted as... 

Consider the following typical reaction in petroleum reforming process ... 

Another important class of reactions, which is common in petroleum reforming reactions, may be represented by the scheme ... 

This reaction was first used in petroleum reformation for the synthesis of higher olefins (Shell higher olefin process - SHOP), with nickel catalysts under high pressure and high temperatures. Nowadays, even polyenes with MW > 250,000 are produced industrially in this way. 

As the work on these first catalysts progressed, it became clear that there was a demand for standardized platinum catalysts more akin to those used in industry. EUROCAT therefore selected two typical petroleum-reforming catalysts manufactured by AKZO, namely, 0.3% Pt/Al203 and 0.3% Pt-0.3% Re/Al203. These were called EUROPT-3 and -4, respectively (Section 11.1.2.2). More recently still, EUROCAT decided to expand its range of standard catalysts to cover oxides... 

As noted above, these are typical petroleum-reforming catalysts [9a, b, 18, 19]. EUROPT-3 is 0.3% Pt AI2O3, and EUROPT-4 contains in addition 0.3% Re. Their surface areas are about 185m2g I, their N2 pore volumes about 0.5 cm3 g-1, and both contain about 1% Cl [18]. 

Xylenes are obtained mainly (80%) from petroleum reformate streams in the form of mixed xylenes. A typical composition of this stream is about 18 percent /7-xylene, 40 percent w-xylene, 22 percent o-xylene, and 20 percent ethylbenzene. The major chemical uses of xylene, however, require the... 

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