| Petroleum resource is non-renewable and drying up gradually, which brought great challenges for ethylene industries, and other new alternative raw materials are desired. The ethanol, produced from biomass fermentation, is a new alternative, also it is regenerative. The technology of ethylene production by ethanol dehydration has presented good perspective and obtained many attentions.In this work, the reaction kinetics for the catalytic dehydration of ethanol to ethylene onγ-Al2O3 catalysts was studied, and a fixed bed of tubular integral reactor was used. The macro kinetic models were obtained: a)-rB=1.065×103e-47.116×103/RT(1-x)1.23 is the host reaction kinetic equation and b)-rC=10.158×e-67.598×103/RT(1-x)0.8473 is the side one.One-dimension andtwo-dimension models were established for the fixed-bed reactor, respectively; the physic properties and model parameters were calculated. In model solution, two-dimension partial differential equations were transferred into ordinary differential equations by using orthogonal collocation method, and the successive solution was by using Runge-Kutta method. The results showed that a) the dehydration of ethanol to ethylene is an endothermic reaction, the axial temperature is slightly lowered along the reactor, with a temperature difference less than 4℃; b) the radial temperature difference is around 5℃; c) the byproduct of ether is very tiny under 410℃, with a molar percentage less than 0.4%; d) the differences of concentration and temperature are very small in reactor radial direction, and the simulated results from two-dimension model and one-dimension model are almost the same, thus, the one-dimension model can be used to simulate the reactor.
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