Hydrogen peroxide propylene epoxidation with

Conjugated propylene epoxidation with hydrogen peroxide is the main reaction proceeding in the temperature range of 500-580 °C under optimal conditions the average propylene oxide yield reaches 50%. 

It is common knowledge that the rate of epoxidation by alkylperoxy radicals is defined by their structure. The simplest representative and the parent radical of this class is the HO radical. In the case of propylene epoxidation with hydrogen peroxide in the gas phase at 500-580 °C and contact time r = 4.4 s, the epoxidating particle is, probably, the HO radical whose activity in the absence of catalysts is higher than the RO activity. 

Effective kinetic and thermodynamic parameters of propylene epoxidation with hydrogen peroxide on biomimic (perFTPhPFe(III)0H/Al203)... 

G. F. Tliiele, E. Roland, Propylene epoxidation with hydrogen peroxide and titanium silicalite catalyst Activitv, deactivation, and regeneration of the catalyst, /. Mol. Catal. A Chem. 117(1997)351. 

Epoxidation with hydrogen peroxide has also been tried. The epoxidation reaction is catalyzed with compounds of As, Mo, and B, which are claimed to produce propylene oxide in high yield ... 

A particularly interesting system for the epoxidation of propylene to propylene oxide, working under pseudo-heterogeneous conditions, was reported by Zuwei and coworkers [61]. The catalyst, which was based on the Venturello anion combined with long-chained alkylpyridinium cations, showed unique solubility properties. I11 the presence of hydrogen peroxide the catalyst was fully soluble in the solvent, a 4 3 mixture of toluene and tributyl phosphate, but when no more oxidant was left, the tungsten catalyst precipitated and could simply be removed from the... 

The number of catalytic cycles (v) in propylene epoxidation reaction with hydrogen peroxide... 

This technology could also be applied for the oxidation of methane (70 °C, 5 Mpa) to formic acid (46% selectivity based on hydrogen peroxide). Another catalyst which can be applied for the direct oxidation of benzene with H202 is the TS-1 catalyst, as described above for propylene epoxidation [41]. Conversion is generally kept low, because introduction of a hydroxy group activates the aromatic nucleus to further oxidation to hydroquinone, catechol and eventually to tarry products [137]. 

The epoxidation of propylene with hydrogen peroxide has been implemented to pilot plant scale (2,000 t/a) by EniChem. The reaction is catalyzed by titanium silicalite-1 (TS-1). Although TS-1 has similar composition to the Ti/Si02 developed by Shell for the epoxidation of propylene with organic hydroperoxides ca. 2.5 wt% Ti, as Ti02) the reactivity is quite different. TS-1 prefers H2O2 and protic solvents, and is almost inactive with hydroperoxides or in apolar media. The reverse holds for Ti/Si02. The reason is found in the different... 

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