采用转动合成方式通过二次生长法在管式α-Al2O3支撑体内表面合成了NaA分子筛膜,采用X射线衍射仪(XRD)、场发射扫描式电子显微镜(FE-SEM)和渗透汽化分离技术对所合成的膜进行了系统表征。考察了合成釜转速对分子筛膜合成的影响,结果表明合成釜转速的提高有利于分子筛膜合成。在转速为4 r·min^-1时所合成NaA分子筛膜分离因子高达2370,渗透通量1.86 kg·h^-1·m^-2左右(乙醇/水溶液质量比为95∶5,343 K)。同时考察了操作温度和进料溶液水含量对NaA分子筛膜渗透汽化性能的影响,初步探讨了端头釉封对膜分离性能的影响。随着操作温度升高,膜的渗透通量增加,而分离因子有所下降;随着进料溶液水含量降低,渗透通量降低,而分离因子呈先上升后下降的趋势。
NaA zeolite membranes were synthesized by the secondary growth method on the inner surface of porous tubular supports using a rotational synthesis vessel.The microstructure of as-synthesized membranes was characterized by X-ray diffraction(XRD)and field emission scanning electron microscopy(FE-SEM).The influence of rotational speed on the performance of zeolite membranes was investigated.Dehydration performance of the membranes was tested by pervaporation of 95∶5(mass)ethanol/water mixtures at 343 K.Separation factor of 2370 and permeation flux of 1.86 kg·h-1·m-2 were achieved through the NaA zeolite membrane synthesized under the rotational speed of 4 r·min-1.The influence of operating temperature and feed concentration on pervaporation performance of the membranes were also investigated,and the glaze sealing of NaA zeolite membranes was discussed preliminarily in terms of the effect on separation performance.It was found that permeation flux through NaA zeolite membranes increased with increasing operating temperature while separation factor declined to a specific value.When decreasing feed water concentration,permeation flux decreased while separation factor increased initially and then declined.