Inorganic Thin Film Membranes for High Temperature Gas Separation

利用硅烷的氧化反应，用化学气相沉积的方法在Vycor玻璃上沉积一层薄薄的二氧化硅。由于CVD反应具有高度的孔扩散限制，所以沉积只发生在孔口。沉积深度可以通过调节温度和压力来控制。根据有关该反应速率的文献数据，在300℃、0.5-5Torr压力下可以沉积约1微米的薄膜。将测量氢和其他气体在复合膜中的扩散系数。此外，将在由复合膜形成的管内进行几个以氢为产物的平衡受限反应，以测试反应器/分离器的想法的可行性。实验的成功可能会导致高温气体分离膜的生产，并有可能实现反应器-分离器的联合。

A thin layer of silica will be deposited on Vycor glass by CVD using the oxidation reaction of silane. The CVD reaction is highly pore-diffusion limited, so the deposition only occurs at the pore mouths. The depth of deposition can be controlled by adjusting the temperature and pressure. From the literature data on the rate of this reaction, a film of approximately 1 micron can be deposited at 300 C at 0.5-5 Torr pressure. The diffusivities of hydrogen and other gases through the composite membrane will be measured. Further, several equilibrium-limited reactions, in which hydrogen is a product, will be carried out in a tube formed by the composite membrane, in order to test the feasibility of the idea of reactor/separator. Success of the experiments could lead to the production of high temperature gas separation membranes and the possibility of a combined reactor-separator.