以廉价高岭土和硅藻土为原料合成方沸石分子筛膜

以廉价高岭土和硅藻土为主要原料，在管状莫来石支撑体上采用2次水热生长法合成了方沸石分子筛膜.通过气体渗透性能测试和XRD、SEM等对膜进行表征，重点考察了合成溶胶中的碱度、合成温度、晶化时间对膜层的晶体形貌和结构以及渗透性能的影响.结果表明:在n（ H2 O）: n（ Na2 O）为200的合成溶胶体系中，合成温度为150℃的条件下晶化反应6 h，可制备出结晶度好且渗透性能较高的纯相方沸石分子筛膜.室温下该膜的氢气渗透率为1.8×10-8 mol·m-2·s-1·Pa-1，H2/CO2气体分离因子为15，高于其努森扩散值（4.7）.

The Synthesis of Analcime Zeolite Membranes from Local Kaolin and Diatomite

The analcime( ANA)zeolite membranes were synthesized on the tubular mullite supports by the seconda-ry growth method using local cheap kaolin and diatomite as silica and aluminum sources. The X-ray diffraction ( XRD),scanning electron microscope( SEM)and gas permeation tests were used to characterize and evaluate the as-synthesized membranes. Several parameters were systematically investigated to evaluate their influence on crystal-lization and gas separation performance of the membranes,including the alkalinity,synthesis temperature and crys-tallization time. The results showed that pure ANA zeolite membranes with high crystallinity and good permeation performance were synthesized at 150℃ for 6 h under the optimized n( H2 O)/n( Na2 O)ratio of 200 in the synthesis sols. The hydrogen permeance and ideal selectivity of H2/CO2 are achieved to 1. 8 × 10 -8 mol·m-2 ·s-1 ·Pa-1 and 15,respectively,which is higher than their Knudsen diffusion values of 4. 7 at room temperature.