Preparation of a zeolite-palladium composite membrane for hydrogen separation: Influence of zeolite film on membrane stability

With the development of hydrogen energy, palladium-based membranes have been widely used in hydrogen separation and purification. However, the poor chemical stability of palladium composite membranes limits their commercial applications. In this study, a zeolite-palladium composite membrane with sandwich-like structure was obtained by using a TS-1 zeolite film grown on the surface of palladium membrane. The membrane microstructure was characterized by SEM and EDX. The effects of the the TS-1 film on the hydrogen permeability and stability of palladium composite membrane were investigated in details. Benefited from the protection of the TS-1 zeolite film, the stability of palladium composite membrane was enhanced. The results indicate that the TS-1-Pd composite membrane was stable after 8 cycles of the temperature exchanging cycles between 773 K and 623 K. Especially, the loss of hydrogen permeance for TS-1-Pd composite membrane was much smaller than that of the pure palladium membrane when the membrane was tested in the presence of C3H6 atmosphere. It indicated that the TS-1-Pd composite membrane had better chemical stability in comparison with pure palladium membrane, owing to its sandwich-like structure. This work provides an efficient way for the deposition of zeolite film on palladium membrane to enhance the membrane stability.