利用水热二次生长法制备用于H_(2)/CO_(2)分离的KAUST-8膜

Preparation of KAUST-8 membranes by hydrothermal secondary growth method for H_(2)/CO_(2) separation

KAUST-8纳米片比表面积和孔隙率较高、铝金属位点丰富,因此具有出色的二氧化碳吸附能力.在本研究中,采用水热二次生长技术,在粗糙的大孔α-Al_(2)O_(3)载体管上,引入氧化铝和硝酸镍作为前驱体,其中,Al_(2)O_(3)用于控制无机支柱[AlF_(5)(H_(2)O)]^(2-)的生长,Ni(NO_(3))_(2)·6H_(2)O用于提高金属前驱体镍源在溶剂中的溶解度,促进Ni(Ⅱ)-吡嗪方格的形成,并与无机柱中心[AlF_(5)(H_(2)O)]^(2-)反应,合成了多晶KAUST-8膜.并进一步探讨了反应物浓度、时间、温度等合成条件以及溶剂对KAUST-8膜性能的影响.优化后的KAUST-8膜的H_(2)渗透率为1.27×10^(-7)mol/(m^(2)·s·Pa)(25℃、0.1 MPa条件下),H_(2)/CO_(2)的理想选择性为19.3.

KAUST-8 nanosheets exhibit high surface area and pore volume,leading to exceptional CO_(2) adsorption due to Al metal sites.In this study,polycrystalline KAUST-8 membranes were developed using a hydrothermal secondary growth technique on coarse microporousα-Al_(2)O_(3) tube supports,employing aluminum oxide and nickel nitrate precursors.Al_(2)O_(3) was to control the growth of inorganic pillar[AlF_(5)(H_(2)O)]~(2-)and Ni(NO_(3))_(2)·6H_(2)O for its enhanced solubility of precursor nickel sources,to form Ni(Ⅱ)-pyrazine square grids which reacted with the pillar to grow KAUST-8 crystals.Additionally,water was used as a solvent to promote membrane growth.Moreover,the synthesis conditions of reactant concentration,time,temperature,and effects of solvents were explored.The resulting optimized KAUST-8 membrane demonstrated H_(2) permeance rate of 1.27×10~(-7)mol/(m^(2)·s·Pa)(at 25℃and 0.1 MPa)and ideal selectivity of H_(2)/CO_(2) of 19.3.