氧化锌改性碳酸钠催化甲醇脱氢制备无水甲醛

用金属氧化物改性Na2CO3催化剂,在连续流动常压固定床反应器中催化甲醇直接脱氢制备无水甲醛。考察了催化剂组成、反应温度及重时空速对催化反应的影响,采用XRD、热重、氮气吸附脱附对催化剂进行表征。实验表明,用机械研磨混合法制备的含氧化锌质量分数为2%的ZnO/Na2CO3催化剂对甲醇脱氢制无水甲醛具有较高的催化活性,在甲醇的进料质量分数为19%、反应温度为650℃、重时空速(甲醇)为7 h-1的反应条件下,甲醇转化率为到57.62%,甲醛的选择性达到77.84%。

Methanol Dehydrogenation to Formaldehyde over Zinc Oxide-Modified Sodium Carbonate

Methanol dehydrogenation to formaldehyde was conducted in a fixed-bed flow reactor under the atmospheric pressure with sodium carbonate modified by metal oxides.The effects of catalyst composition,reaction temperature,weight hourly space velocity(WHSV) on the reaction were investigated.The catalysts were characterized by XRD,TG,and Nitrogen adsorption.The results indicated that the superior catalytic activity for methanol dehydrogenation to formaldehyde was obtained with ZnO/Na2CO3 containing 2% ZnO prepared by mechanical grinding method.The conversion of methanol and the selectivity of formaldehyde were respectively 57.62% and 77.84% under the condition of wmethanol/wfeed=0.19,reaction temperature 650 ℃ and WHSV(methanol) 7 h-1.