Propylene oxide, -, synthesis

There are two important methods for the manufacture of propylene oxide, each accounting for one half the total amount produced. The older method involves chlorohydrin formation from the reaction of propylene with chlorine water. Before 1969 this was the exclusive method. Unlike the analogous procedure for making ethylene oxide from ethylene, which now is obsolete, this method for propylene oxide is still economically competitive. Many old ethylene oxide plants have been converted to propylene oxide synthesis. 

Figure 7.11 presents the mechanism of propylene oxide synthesis by allyl alcohol isomerization. This assumption correlates well with experimental data the kinetic curve shape... 

Figure 7.13 The mechanism of intermediate C3H6Fe3+PP0H/Al203 transformation. Continuous arrows propylene oxide synthesis and dashed arrows allyl alcohol synthesis.

Propylene oxide synthesis, 34 Pseudoplasticity, 71, 103, 104 Psvchrometiic chart. 232 application example, 234... 

Key Words Propylene oxide synthesis, Propylene epoxidation with ethylbenzene hydroperoxide, fe/ f-butyl hydroperoxide, cumene hydroperoxide. Preparation of Ti/Si02, Ti/MCM-41, Ti/MCM-48 catalysts, Chemical vapor deposition, 1,2-Epoxyoctane synthesis. 2008 Elsevier b.v. 

Styrene is obtained almost exclusively by dehydrogenation of ethyl benzene, and in small quantities by the dehydration of a-methyl benzyl alcohol, the by-product of the propylene oxide synthesis from propylene and a-methyl benzyl hydroperoxide. Styrene can be polymerized free radically, cationically, anionically, and with Ziegler-Natta catalysts. Only the free radical polymerizations have commercial significance. 

Propylene is the starting material for the commercial propylene oxide synthesis. Direct oxidation only provides low yields, consequently the propylene is stoichiometrically oxidized with hydroperoxides such as /-butyl hydroperoxide or a-methyl benzyl hydroperoxide. Alternatively, hydrogen chloride can be eliminated from propylene chlorohydrin, CHa—CH(OH)—CH2CI. 

The yields shown by Table II are somewhat lower than those alreatfy reported for the propylene oxide synthesis using preformed hydrogen peroxide (12). However, due to the preliminary nature of the experiments carried out... 

Gas-liquid Bubble column Chlorohydrin process for propylene oxide synthesis... 

Karakhanov, E.A. Kardasheva, Y.S. Maksimov, A.L. Predeina, V.V. Runova, E.A. Utukin, A.M. (1996) Macrocomplexes on the basis of functionalized polyethylene glycols and copolymers of ethylene-oxide and propylene-oxide synthesis and catalysis, J. Mol. Catal A - Chem., 107,235-40. 

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