Propylene epoxidation

After epoxidation, propylene oxide, excess propylene, and propane are distilled overhead. Propane is purged from the process propylene is recycled to the epoxidation reactor. The bottoms Hquid is treated with a base, such as sodium hydroxide, to neutralize the acids. Acids in this stream cause dehydration of the 1-phenylethanol to styrene. The styrene readily polymerizes under these conditions (177—179). Neutralization, along with water washing, allows phase separation such that the salts and molybdenum catalyst remain in the aqueous phase (179). Dissolved organics in the aqueous phase ate further recovered by treatment with sulfuric acid and phase separation. The organic phase is then distilled to recover 1-phenylethanol overhead. The heavy bottoms are burned for fuel (180,181). 

In the organic chemicals industry, H2O2 is used in the production of epoxides, propylene oxide, and caprolactones for PVC stabilizers and polyurethanes, in the manufacture of organic peroxy compounds for use as polymerization initiators and curing agents, and in the synthesis of fine chemicals such as hydroquinone, pharmaceuticals (e.g. cephalosporin) and food products (e.g. tartaric acid). 

Peroxides actually or potentially used to epoxidize propylene ... 

Propylox [Propylene oxidation] A process for epoxidizing propylene to propylene oxide (1,2-epoxypropane),... 

A homogeneous catalytic process, developed by Oxirane, uses a molybdenum catalyst that epoxidizes propylene by transferring an oxygen atom from tertiary butyl hydroperoxide. This is shown by 8.28. The hydroperoxide is obtained by the auto-oxidation of isobutane. The co-product of propylene oxide, /-butanol, finds use as an antiknock gasoline additive. It is also used in the synthesis of methyl /-butyl ether, another important gasoline additive. The over-... 

In some cases, an important contribution ofhomogeneous radical reactions to PO formation is postulated [32f] in practice, an allyl radical is initially formed at the catalyst surface, tvhich then interacts tvith O2 to form peroxy radicals, leading to the formation of peroxodimers or hydroperoxides. The hydroperoxides epoxidize propylene to PO and the peroxodimers may decompose to form PO. 

Key Words Direct propylene epoxidation. Propylene oxide, Gold, Titanium, Propene, Au/Ti catalysts. Catalysis by gold. Titanium silicalite, TS-1, Gold/TS-1, Hydrogen peroxide, Kinetics, Design of experiments, Deposition-precipitation, Ammonium nitrate, Selective oxidation, Alkene epoxidation, Density functional theory, DFT calculations, QM/MM calculations. 2008 Elsevier B.v. 

Polyether-polyols are produced by the poiyaddition of an epoxide (propylene or ethylene oxide) to an active hydrogen initiator (polyol, amine, add. water, etc.). Polypropylene glycol PPG) is obtained by the poiyaddition of propylene oxide to propylene glycol, used as an initiator ... 

The Mo(VI) and W(VI) complexes of structure 1 selectively epoxidize propylene and other olefins at room temperature in non-coordinating solvents such as e.g. dichloroethane [1,2]. 

The indirect propylene oxidation process via ethylbenzene hydroperoxide (Halcon process) is displayed in Eq. (6.12.12). Ethylbenzene, obtained by the acid-catalyzed Friedel-Crafts alkylation of benzene with ethylene, is converted with air into ethylbenzene hydroperoxide. The hydroperoxide epoxidizes propylene and generates the co-product a-phenylethanol that is later dehydrated to styrene. Styrene is a major industrial chemical used mainly as monomer for polymers such as polystyrene or styrene-containing copolymers ... 

Propylene oxide is another basic chemical, used in manufacturing intermediates for urethane foams (used in cushioning and insulation) and brake and hydraulic fluids. The volume of propylene oxide produced increased from 310 million pounds in 1960 to 3.2 billion pounds in 1990. The classical industrial synthesis has been the reaction of chlorine with propylene to produce the chlorohydrin, followed by dehydrochlorination with caustic to produce the epoxide, propylene oxide, plus salt. In this case, both... 

Common name epoxidized propylene glycol dioleate ... 

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