(1. State Key Laboratory of Porous Metals Materials, Northwest Institute for Non-ferrous Metal Research, Xi’an 710016, China) (2. State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong Univeristy, Xi’an 710049, China)
In this paper, static hydrogen permeation experiment of multicomponent palladium （Pd） alloy membranes was investigated in hydrogen gas with the presence of 0.1vol% methane gas. The influences of methane gas on Pd alloy membranes at high temperatures (450, 550, and 650 ℃) and high pressures (1, 10 MPa) were studied. Surface morphologies, microstructures and surface states of Pd alloy membranes were characterized and analyzed by SEM, metallurgical microscope and XPS. The results show that the quality of Pd alloy membrane is almost unchanged after being exposed in hydrogen gas with the presence of 01% methane gas. Furthermore, there is no variation on the surface morphology of Pd alloy membranes. XPS analysis shows that methane gas has no effect on the surface chemical state of Pd alloy membrane. Characterization peak of either carbides or decomposition was not observed. Carbon is adsorbed on the surface of Pd alloy membrane existing in the form of —CH—. Compared with low temperature and low pressure condition, there is a little methane gas absorbed on the surface of Pd alloy membrane under high temperature and high pressure. It might result from that the competitive adsorption between methane and hydrogen on the surface of Pd alloy membrane at high temperature and high pressure is very weak, which could be ignored.