γ-Al2O3催化剂上乙醇脱水制乙烯的实验研究

考察了低浓度乙醇在固定床管式反应器中活性氧化铝上催化脱水生成乙烯的反应行为。研究了反应温度、进料流率、乙醇浓度等因素对反应行为的影响规律。结果表明，在410～440℃范围内催化剂对主反应的选择性随着温度的升高而升高，在达到一定的温度后趋于稳定。乙醇转化率对温度并不敏感，而随空速的增大而降低。催化剂选择性随着进料流率增大而增大，之后稳定在99.5%以上。在进料流率小于1mL/min时乙醇转化率高于85%，乙烯收率均在80%以上。当利用低浓度乙醇作原料时，乙醇转化率随乙醇浓度增大而增大，催化剂选择性维持稳定。最终选定的适宜工艺条件：温度420℃左右，进料流率1.0mL/min左右。

Experimental study of the catalytic dehydration of ethanol to ethylene on a γ-Al2O3 catalyst

The catalytic dehydration of ethanol to ethylene on a γ-Al₂O₃ catalystin a fixed bed reactor has been studied. The influence of varying the reaction temperature, feed flow rate, and concentration of ethanol was investigated systematically. The results show that in the temperature range 410 to 440℃, the selectivity of the γ-Al₂O₃ catalyst increases with reaction temperature at first and then remains constant, whilst, the yield of ethylene is not very sensitive to the reaction temperature over the entire range. The optimum temperature is about 420℃. As the feed flow rate decreases, the selectivity increases to nearly 100%, but the conversion decreases. The yield of ethylene is above 80% when the feed flow rate is less than 1.0mL/min. According to the experimental results, the optimum feed flow rate is about 1.0mL/min, and the optimumconcentration of ethanol is in the range 50% to 100%. At all ethanol concentrations, the yield of ethylene is 88% or higher, and the selectivity remains stable.