| Along with the more and more use of poly vinyl chloride (PVC) in our daily life, the vinyl chloride monomer (VCM), which is the main raw material of producing poly vinyl chloride, became a very important chemical product. How to produce VCM efficiently became one of the main subjects of all the countries in the world. Nowadays, there are mainly three ways of producing VCM, that is ethylene oxychlorination, acetylene oxychlorination and ethane oxychlorination. The reactants of ethane oxychlorination are consisted of C2H6, HCl and air. As the resource of C2H6 is abundance, cost of this route is much lower, therefore it will be a promising way to produce VCM.This thesis mainly discusses the preparation of ethane oxychlorination catalysts and the evaluation of their capability. It mainly consists of four parts as follow: preparation of the catalysts; apparatus and condition of the reaction ; factors which affect the capability of the catalysts; characterization and discussion of the catalysts.We useγ-aluminum oxide as support, and the active components of the catalysts include CuCl2.2H2O, KCl and rare earth(La,Ce,Pr,Nd,Sm) oxides. The catalysts are prepared by impregnation method.We adopt a quartz tube as the reactor of the ethane oxychlorination. The products of this reaction are C2H4, C2H3Cl, CO, CO2, C2H5Cl, etc. The products can be analyzed by FID tester. The column oven is heated by means of temperature program from 40℃ to 160℃ with a rate of 8℃/min, and temperature of the tester is 180℃.The results are marked down by register instrument.Based on some literature and many experiments, we have decided an appropriate reaction conditions: the reaction temperature is 500℃, the contact time is 2~4 seconds, the mass percent of Cu is 5%, and the mass percent of K is 6%. Under these conditions, C2H6 conversion can reach 95%, C2H4 selectivity can reach 55%, and C2H3Cl selectivity can reach 30%.Many factors can more or less affect the capability of the catalysts, such as composition of the catalysts, reaction temperature, flow rate of feed gases, contact time, and so on.We have done a series of reactions on catalysts of lanthanum (1%,3%,5%,7%,9%) and praseodymium (1%,3%,5%,7%,9%) under the same conditions, in order to study the effect of the rare earth on capability of the catalysts.We also have discussed the life-time of La(3% and 5%) catalysts. The catalyst which contains 3% lanthanum has 30h life-time. The catalyst which contains 5% lanthanum has 100h life-time and shows good catalytic activity and stability.We characterize the structures of the catalyst by XRD, BET, TG-DTA, ICP, SEM, etc. From XRD results, we can find that the intensity of the diffraction peaks of KCl and γ-aluminum oxide after the reactions is different from that before reactions. For most catalysts, the intensity of KCl diffraction peaks weakens after the reactions. The causes of this change may be the destroy of the KCl crystal or the loss of KCl, which can result in the inactivity of the catalysts.BET test results show that the BET surface area of the catalysts which load active components is smaller than that of pureγ-Al2O3. Because some particulates go into the holes of γ-Al2O3. This physical area is not always the effect area which can catalyze the reaction, but that contains active components is the effect area.We have done reactions on La3%,5% and 7% catalysts separately. After they reacted 10h, 20h and 40h, we took out some sample and did TG-DTA analysis. There are mainly three kinds of peaks in the charts: desorption peak of the adsorbed water, which appears under 200℃; at about 333℃ shows a peak formed by combustion of carbon deposition on metals of catalysts; at 765℃ or so appears another kind of peak which is formed by combustion of deposited carbon on acid centers of catalysts. The latter kind of deposited carbon is much different to combust, unless under high temperature.From the pictures of SEM, we can obviously observe that before reactions, the catalyst components distribute eq...
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