Study On Reaction At VLE And Phase Behavior Of Multicomponent Mixture Based On Etherification System Of Light Gasoline

The rapid development of the automobile industry had resulted in seriouspollution of automobile exhaust on the atmosphere. In order to reduce this pollution,lead-free, oxygen and high-octane gasoline was demanded. Some ethers such asmethyl tertiary butyl ether (MTBE) and methyl tertamyl ether (TAME) had highoctane, didn’t release harmful substances, which had been widely recognized aroundthe world. The etherification reaction used successfully reactive distillationtechnology. Reactive distillation was a new chemical engineering process developedat1980s. There were some advantages of reactive distillation over the conventionalprocess: less investment, high conversion rate and low energy consumption.Themodynamics and kinetics data were essential in the process of reactivedistillation and equipment design. More and more researchers focused on thethemodynamics and kinetics of the etherification reaction of methanol withhigh-carbon olefins (more than C5). However, most of the vapor-liquid equilibrium(VLE) data were measured at atmospheric pressure. So far, there was almost no reporton isothermal VLE data for methanol with high-carbon olefins in the open literatures,and no report of the experimental reactive VLE data of the system on light gasolineetherification.A set of experimental device was designed and manufactured in this paper.Firstly, the binary isothermal VLE data of methanol+2,3-dimethyl-1-butene(DM1B),and methanol+2,3-dimethyl-2-butene(DM2B) were measured with the device at fourdifferent temperatures. The pressures of the two systems were achieved to618.6kPaand498.9kPa, respectively. So the data were more practical than that of atmosphericpressure.Secondly, the reactive VLE data were directly measured for the systems ofetherification reaction of methanol with2-methyl-1-butene (2M1B) and2-methyl-2-butene (2M2B) in the presence of the macroporous sulfonic ion exchangeresin (D005). The reactive VLE data were calculated with the parameters of Wilsonmodels regressed from this paper and literature, respectively. And the averagedeviation between this paper and literature was0.0111. The result showed that thedata calculated with the regression parameters from experimental data in this paperwere closer to the experimental value. It was shown that muiti-components interactionparameters in activity coefficient models and reaction equilibrium constants can be obtained simultaneously by the measurement of reaction VLE, and the data is moreaccurate in the design of reactive distillation.Finally, the macro-kinetics data of methanol and isoamylene were measured atthe bubble point temperature of reactant. The parameters in the equation of theconversion rate of isoamylene with the reaction time were obtained. The mechanismof etherification reaction and adsorption of reactants on the catalyst D005werecalculated by Gaussian software. It was shown that the mechanism of theetherification reaction for methanol with isoamylene was in accord withLangmuir-Hinshelwood (L-H) hypothesis.