A Study of Ethanol Dehydrogenation Reaction in a Palladium Membrane Reactor

• Main Authors: Jay-Yu Tsai, 蔡杰裕
• Other Authors: none
• Format: Others
• Language: en_US
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/31395382330522119812

碩士 === 逢甲大學 === 化學工程學所 === 90 === Abstract The dehydrogenation of saturated hydrocarbons to alkenes used as an intermediate in the production of new fuels and fuel additives, and hydrogen has become more and more popular in the past several decades. In this paper, we investigated the ethanol dehydrogenation to produce acetaldehyde and hydrogen in a palladium membrane reactor. With the separation of hydrogen by permeation through a palladium membrane, the thermodynamic equilibrium was allowed to displace to a new condition. It cannot only shift the equilibrium to increase the conversion, but also obtain the high purity of hydrogen from the permeation side. The reactor used a porous stainless steel tube that was electrolessly plated palladium with a thickness c.a. 15μm, was industrial catalyst loaded MDC-3 for the dehydrogenation test. With the change between the operation parameters, we can find the optimum operation condition in a palladium membrane reactor, and compare with conventional reactor. According to the experimental data, the maximum production of pure hydrogen obtained was 0.0281mole/h and the maximum palladium membrane recovery yield of hydrogen form ethanol was found to be 76.9﹪. For the dehydrogenation of ethanol to acetaldehyde in a dense membrane reactor, the largest enhancement in ethanol conversion was a factor of 1.49 greater than a porous membrane reactor, 1.57 greater than equilibrium conversion and 1.95 greater than a conventional reactor. But it still had a large difference between the experiment and the simulation data. The experimental result was much lower than simulation that was attributed: 1.the effect of sweep is ignored. 2.The low activity and low acetaldehyde selectivity catalyst. 3. Existence of by passing and challenge effect that caused inadequate contact between the reactant, catalyst bed and the membrane surface.