Cu/ZrO2催化剂上乙醇水蒸气重整反应的研究: Ⅱ 反应条件的影响

采用沉淀法或醇凝胶法、浸渍法制备Cu/ZrO2催化剂，在常压微型固定床石英管反应器上进行乙醇水蒸气重整反应，采用程序升温还原（TPR）技术表征催化剂的还原特性。考察了催化剂还原温度、反应温度、水醇比、空速等对反应的影响以及催化剂的稳定性。结果表明，在300℃～500℃，随反应温度升高，乙醇转化率增大，H2选择性下降。不同还原温度对转化率的影响不是很大，对于H2选择性，300℃、400℃还原的催化剂优于500℃还原的催化剂。高水醇比有利于提高转化率和H2选择性。随空速增大，转化率和H2选择性呈现下降的趋势。8%Cu/ZrO2催化剂在400℃或450℃反应22h显示出良好的稳定性。

Steam reforming of ethanol over Cu/ZrO2 catalysts Ⅱ Influences of reaction conditions

In the previous paper, the catalytic performances of Cu/ZrO2 and the effects of the catalysts preparation parameters on the steam reforming of ethanol were investigated. In this paper, the influences of the reaction conditions on the reaction are further examined. Cu/ZrO2 catalysts were prepared by precipitation/alcogel and impregnation methods. The ethanol steam reforming reactions were carried out in a flow-type fixed bed micro-reactor (quartzes tube) at atmospheric pressure. The catalysts were also characterized by H2-TPR. The influences of the reduction temperature of the catalysts, reaction temperature, water/ethanol ratio and space velocity on the steam reforming of ethanol and the stability of Cu/ZrO2 catalyst were investigated. The results showed that the conversion of ethanol increased while H2 selectivity decreased with the increase of the reaction temperature in the range of 300℃～500℃. The influence of the reduction temperature of the catalysts on the conversion was not significant, although the reduction at 300℃ or 400℃ was favorable for the H2 formation in the reaction. High water/ethanol ratios resulted in the high ethanol conversion and high H2 selectivity. With the increase of space velocity, the ethanol conversion and H2 selectivity decreased. 8％Cu/ZrO2 showed relatively high stability for 22h at 400℃~450℃.