NaA分子筛膜渗透蒸发制备高纯糠醛

Preparation of High-Pure Furfural Through Pervaporation on NaA Zeolite Membranes

采用热浸渍晶种法制备了均匀致密的NaA分子筛膜,并用于糠醛脱水。考察了进料流量、进料温度和进料中糠醛含量对糠醛脱水性能的影响。实验结果表明,当进料温度为80℃、渗透侧压力小于100 Pa、流量为196 mL/min、进料中糠醛含量为93.7%(w)时,NaA分子筛膜对于水-糠醛的分离因数最高可达34 110;当进料温度为90℃时,分离因数约为12 000,膜的渗透通量可达1.79 kg/(m2.h);对进料中糠醛含量为89.6%(w)的水-糠醛混合液进行渗透蒸发浓缩,连续运行96 h后所得产品糠醛含量为99.5%(w),膜的平均渗透通量为0.60 kg/(m2.h)。

Continuous and compact NaA zeolite membranes were synthesized by a hot dip-coating seeding method and applied to the preparation of high pure furfural by dehydration. The effects of feeding flowrate, feedstock temperature and furfural content in the feedstock on the dehydration of furfural were investigated. The results indicated that under the conditions of feedstock temperature 80 ℃, pressure of the penetrating side less than 100 Pa, feeding flowrate 196 mL/min and furfural content in the feedstock 93.7%（w）, the separation factor of the NaA membranes could reach 34 110. Under the conditions of feedstock temperature 90 ℃ and separation factor 12 000, the flux could reach 1.79 kg/（m^2·h）. The furfural content in the products was 99.5%（w） and the average penetration flux on the membranes was 0.60 kg/（m^2·h） when the furfural content in the feedstock was 89.6%（w） and after continuous pervaporation was carried out for 96 h.