二次生长法在大孔管状载体上制备[Co(Im)_2]_∞膜

Preparation of[Co(Im)_2]_∞ membranes on macroporous supports by secondary growth method

以水为溶剂在室温条件下制备出大小为500nm的[Co(Im)2]∞晶体,粒径分布比较均匀,适宜作为成膜的晶种.利用二次生长法在大孔管状α-Al2O3载体上制备致密连续的[Co(Im)2]∞膜,并考察了成膜时间、合成液浓度对成膜的影响.采用SEM,XRD和单组分气体测试对膜的形貌和气体分离性能进行表征.通过SEM显示[Co(Im)2]∞膜无缺陷,膜层厚度约为9μm.由单组分气体渗透测试可知,室温条件下H2的渗透通量达到1.1×10-8 mol/(m2·s·Pa),H2/CO2,H2/N2和H2/CH4的理想分离系数分别7.8,9.1和7.9,超过努森扩散系数.

[Co（Im）2]∞ seeds with size of 500 nm were obtained in aqueous solution at room temperature.The characterization of the seeds by SEM,XRD showed that the [Co（Im）2]∞ crystals with uniform particle size distribution is suitable as seeds for the selected macroporous support.Through secondary growth method in aqueous solutions,continuous and crack-free [Co（Im）2]∞ membrane was successfully obtained on the low-cost macroporous α-Al2O3 support,exhibiting H2 permeance of 1.1 × 10-8rmol/（m2 · s · Pa）,with ideal selectivities for H2/CO2,H2/N2 and H2/CH4 systems of 7.8,9.1 and 7.9.Moreover,The effects of some parameters including the concentration of solution and synthesis times on the formation of [Co（Im）2]∞ membranes were investigated.