NaA沸石膜渗透蒸发脱除二氯甲烷中的痕量水

Removal of Trace Water from Dichloromethane by Pervaporation with NaA Zeolite Membrane

利用热浸渍法在α-Al2O3载体管外表面预涂晶种,水热合成了NaA沸石膜;采用NaA沸石膜进行了分离水-二氯甲烷的研究。考察了进料流量、渗透侧压力和进料温度对水的渗透通量和分离因数的影响。实验结果表明,合成的NaA沸石膜厚度约为24μm,与载体结合紧密,膜连续且致密;随进料流量的增加,渗透通量和分离因数均增大;随渗透侧压力的增大,渗透通量减小,分离因数未发现明显变化;随进料温度的升高,渗透通量增大,分离因数减小;在进料流量198 mL/min、进料温度25℃、渗透侧压力0.1 kPa、进料侧压力0.1 MPa的条件下,水的渗透通量和分离因数分别达到0.172 kg/(m2.h)和39 900。

NaA zeolite membranes were hydrothermally synthesized on the outer surface of tubular α-Al2O3 with seeding by a hot dip-coating method.The NaA zeolite membranes were applied to removal of trace water from dichloromethane.The influences of the feed flow,permeation side pressure and feed temperature on the water flux and the separation factor were investigated.The results showed that the synthesized membranes with thickness about 24 μm were continuous and dense,and were combined firmly with the α-Al2O3 substrate.With the feed flow increasing,both the permeation flux and the separation factor increased.With the permeation side pressure increasing,the permeation flux decreased and the separation factor did not change significantly.With the feed temperature rise,the permeation flux increased but the separation factor decreased.Under the conditions of feed flow 198 mL/min,feed temperature 25 ℃ and permeate side pressure 0.1 kPa,feed side pressure 0.1 MPa,the water permeation flux and the separation factor could reach 0.172 kg/（m2·h） and 39 900,respectively.