| Ethylene is an essential material for the petrochemical industry. One country'sdevelopment level of petrochemical can be determined by the yield of ethylene. Our demandof ethylene is increasing day by day. Today the world production of ethylene is mainly fromnaphtha cracking or the cracking of ethane extracted from natural gas. Petroleum prices areincreasing, this factor give the ethylene business some limits. An conventional route ofbioethanol dehydration have attracted the attention of all the world. This route increasesdomestic employment and avoids use of petroleum feedstock, which frequently has to beimported, also avoids the pollution of environment. In our country, catalytic dehydration ofbioethanol into ethylene was always using Al2O3 which requires higher temperature (470℃)and lower WHSV (0.1～0.3h-1), this can increase the costs. The aim of this paper is to studya new catalyst for bioethanol dehydration which has good capability of dehydration.In the experiment, we have discovered that the streamed ZSM-5 was more efficiencythat was not streamed. Because the catalysts treated by stream can remove Al of frameworkand strong acid sites. This can avoid byproduct and also increase the efficiency of industry.Then a new catalyst which Ce have been incorporated has been discovered. A lot of factorssuch as temperature,WHSV,concentration of raw material and different modified methodhave been discussed. As the result shows that the optimal reaction conditions are as follow:temperature (250-300℃),the WHSV (1-3h-1), 1 atm, the catalyst is nano-scale HZSM-5which 3％CeO2 have been incorporated. And in these conditions, run for 2000 hours, theyield of ethylene is also 95％, and the selectivity of ethylene is no less than 96％.
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