Development of Molecular Sieving Inorganic Membranes and Separation System for High Temperature Gases

有机膜可以用于在高温度下的气体分离，在氧化大气层中，有机膜不耐药性。在准备分子密封具有高渗透性的非有机薄膜时，码头结构应该受到严格控制。在本研究中，陶瓷和钯薄膜是由新颖的制备方法、气体渗透性和热化学稳定性以及对薄膜进行了测试，钯薄膜是由交叉流动CVD方法制成的。Hydrogen permeance and selectivity to nitrogen were respectively higher than 10^\-6> mol·m^\-2>s^\-1>Pa^\-1> and 1000。该膜是对氢的安置和硫酸中毒的抵抗力。Silica膜也是由使用四乙基正酰盐的相同程序编写的。薄膜在蒸汽中稳定，并显示出氢到氮的选择性高于1000。Furthermore、硅基微膜是由在伽马-氧化铝-修改的支持管上制备的多碳水化合物的控制性幽门螺杆菌制成的。该膜展示了氢到硝基的全选择性高于Knudsen的价值，而且可使用多达400个C. Perovskite氧化物膜是由盐凝胶方法和slicalite膜制成的，由羟基合成，尊重地。碳二氧化物最好通过这些薄膜由于表面扩散而被充分利用，但CO_2渗透的选择性是不充分的。进一步的针头--尺寸控制是工业用途所必需的。

Inorganic membranes can be used for gas separation at high temperature in an oxidative atmosphere where organic membranes are not resistant. In preparing molecular sieving inorganic membranes with high permeability, the pore structure should be strictly controlled. In this study, ceramic and palladium thin membranes were formed by novel preparation methods, and gas permeability and thermal and chemical stability of the membranes were examined.Palladium thin membrane was formed in macropores of an alpha-alumina support tube by cross-flow CVD method. Hydrogen permeance and selectivity to nitrogen were respectively higher than 10^<-6> mol・m^<-2>s^<-1>Pa^<-1> and 1000. The membrane was resistant against hydrogen embrittlement and sulfur poisoning. Silica membrane was also prepared by the same procedure using tetraethylorthosilicate. The membrane was stable in steam and showed a selectivity of hydrogen to nitrogen higher than 1000. Furthermore, Silica-based microporous membrane was prepared by controlled pyrolysis of polycarbosilane coated on a gamma-alumina-modified support tube. The membrane showed a permselectivity of hydrogen to nitrogen higher than the Knudsen value and was usable up to 400ﾟC.Perovskite oxide membrane was prepared by sol-gel methods and slicalite membrane formed by hydrothermal synthesis, respectively. Carbon dioxide was preferentially permeated through these membranes because of the surface diffusion, but the CO_2 permselectivity was insufficient. Further pore-size control is needed for the industrial uses.