Dehydrogenation, butene cyclohexane

The compensation trend present in data reported by Shannon et al. (285) for the isomerization of n-butenes over a number of different oxide catalysts is given in Table V, P (omitting from the calculation the point for MnO, which shows a marked deviation). Dehydrogenation of cyclohexane over oxides (286) exhibited similar behavior the calculated line is given in Table V, Q. Hydrocarbon exchange over alumina (287) also gave a slight compensation trend, for which e = 0.132 and ae = 0.024. 

Itoh and his co>investigators have developed a number of packed>bed Pd>based membrane shelUand-tube reactors for various reactions dehydrogenation of cyclohexane, ethylbenzene, and 1-butene and water-gas shift reaction. Oertel et al. 

Further gas-phase studies include the work of Maria et al., who used an isothermal differential microreactor to study the dehydrogenation of cyclohexane and its methyl derivatives [25]. Ye et al. fabricated a Pd membrane microreactor from a silicon wafer using surface and bulk micromachining to study the hydrogenation of 1-butene [19]. 

Because hydrogen can easily be removed from a reaction stream, many dehydrogenations have been studied. These include dehydrogenation of methane to carbon,326 ethane to ethene,327,328 propane to propene,329 n-butane to butenes,330 isobutane to isobutene,331,332 cyclohexane to benzene,332-334 meth-ylcyclohexane to toluene 335 n-heptane to toluene,336 methanol to formaldehyde,330 and ethanol to acetaldehyde.337... 

Cyclohexane is rly easily dehydrogenated into benzene, and even at very low extents of reaction, stoichiometry reaction (6) can be replaced by the secondary stoichiometry reaction (12). For cyclohexane, the constituents are (apart from cyclohexane) hydrogen, methane, ethane, ethylene, acetylene, propene, 1-butene, 1,3-butadiene, cydohexene, and benzene [3]. However, one can check that the equations written are independent, using the Jouguet [IS] criterion, (t.e., if/ = n-o)). In this criterion, the number of the independent constituents, 1//, for a chemical system is equal to the required constituents. n, (i e., H3, Cl, C3, CsHe, Q, C4, Cj. c-Q, CaJ, subtracting the number of independent stoichiometric equations. q>. 

The best olefin yields were observed over Pt-coated monoliths. In the case of ethane/02 mixtures, selectivities to ethylene up to 65% at 70% ethane conversion and complete O2 conversion were reported." The oxidative dehydrogenation of propane and -butane produced total olefin select vies of about 60% (mixtures of ethylene and propylene) with high paraffin conversions." " Mixtures of ethylene, propylene and 1-butene were observed by the partial oxidation of -pentane and n-hexane ethylene, cyclohexene, butadiene and propylene were the most abundant products of the partial oxidation of cyclohexane." ... 

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