Kinetic Study For The Preparation Of Ethylene By Selective Dehydration Of Ethanol On The γ-Al₂O₃ Catalyst

The conditions of selective catalytic dehydration of ethanol to ethylene on theγ-AlO catalyst in a fixed bed reactor were studied. The influence of reaction temperature, feed velocity, and the concentration of ethanol was investigated systematically.The results showed that the selectivity ofγ-AlO increases with the raise of the reacting temperature, the yield of ethylene is not very sensitive to the reaction temperature in the range from 410℃to 440℃, and the suitabletemperature is about 420℃. The selectivity ofγ-AlO increases and reaches to nearly 100% as the feeding velocity ascends, but the conversion of ethanol decreases. The yield of ethylene is above 80% when the feeding velocity is less than 1．0ml/min. So it seemly shows that the suitable feeding velocity is about 1．0ml/min. The concentration of ethanol from 50% to 100% can be all available for the reaction. The selectivity ofγ-AlO is stable, but the conversion of ethanol declines with the dropping of the concentration of ethanol. The yield of ethylene all reached to 88% or even higher in theexperiments. The macro kinetic experiments of ethanol to ethylene withγ-AlO catalyst were carried out in a fixed bed integral reactor under the following conditions: 1atm, 410℃～440℃, ethanol concentration of 25%～100%.Kinetic models were then established, and the related parameters were estimated according to the experimental data, and the statistical test results showed that the macro kinetic models established forγ-AlO not only agreed with experimental data well, but were highly acceptable and reliable also.