Propylene disproportionation

Propylene Disproportionation. A commercial plant utilizing the disproportionation of propylene to ethylene was built in 1966 by Gulf Oil of Canada Ltd. utilizing technology developed by Phillips. 

Propylenediamine, 8 485 physical properties, 8486t pK values, 8487t prices of commercial, 8496t typical specifications, 8496t Propylene disproportionation process,... 

Fig. 1. Relation of product distribution to calculated contact time in propylene disproportionation. Data obtained in tests at 163 C and 450 p.s.i.g. with C0O-M0O3-AI2O3 catalyst and 60 propylene-40 propane feed (Ref. 1)...

The calculated thermodynamic equilibrium conversions and product compositions for propylene disproportionation at 200 to 400 C were reported by Heckelsberg, Banks, and Bailey16). Atlar, Pis man, and Bakhshi-Zade 8S) made similar calculations for the 50 - 300 °C range. They noted that the equilibrium constants were independent of pressure. Banks and Regier 57) showed thermodynamic equilibrium conversions as a function of temperature for the various reactions involved in the synthesis of isoamylene via disproportionation (Fig. 3). A comparison of calculated equilibrium composition for... 

Moffat, Johnson, and Clark86)found the propylene disproportionation reaction on tungsten oxide-silica catalyst to be limited by interphase diffusional effects in spite of calculations which predict that no diffusional limitation should occur. They postulate that widely separated and very active sites could have their inherent activity limited by localized film diffusional effects which are functions of Reynolds and Schmidt numbers. Activity of cobalt molybdate-alumina was not limited by interphase or prediffusional effects. 

PF/PF, PM/PM Adiabatic Isothermal Shell side Af->B ethylbenzene dehydrogenation HI decomposition, propylene disproportionation 8l cyclohexane dehydrogenation Mohan Govind. 1988b Mohan Govind. 1988c... 

Mohan and Govind [1988c] applied their isothermal packed-bed porous membrane reactor model to the same equilibrium-limited reaction and found that the reactor conversion easily exceeds the equilibrium value. The HI conversion ratio (reactor conversion to equilibrium conversion) exhibits a maximum as a function of the ratio of the permeation rate to the reaction rate. This trend, which also occurs with other reactions such as cyclohexane dehydrogenation and propylene disproportionation, is the result of significant loss of reactant due to increased permeation rate. This loss of reactant eventually negates the equilibrium displacement and consequently the conversion enhancement effects. 

Mohan and Govind [1988c] have also studied propylene disproportionation to form ethylene and butene... 

Cyclohexane dehydroge- Same as above, nation, HI decomposition, propylene disproportionation/... 

The search continues for better and more economical processes for the production of ethylene. Those processes include catalytic thermal cracking, methanol to ethylene, oxidative coupling of methane, advanced cracking technology, adiabatic cracking reactor, fluidized bed cracking, membrane reactor, oxydehy-drogenation, ethanol to ethylene, propylene disproportionation, and coal to ethylene. Much work is still needed before any such process can compete with current processes. 

Keywords propylene disproportionation, dispersion, heptamolybdate, sublimation... 

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