H2 permeance and surface characterization of a thin (2 μm) Pd-Ni composite membrane prepared by electroless plating

The high cost of palladium membranes limits their widespread use in industrial applications. We report a novel strategy for the preparation of economic hydrogen separation membranes. In this study, a Pd88-Ni12 composite membrane was prepared with a considerable nickel content (>10 wt%) for the first time using the organ-ic-inorganic activation method in the ELP approach. The H2 permeance of the Pd88-Ni12 composite membrane was 4.34 x10-7 mol m2 s1 Pa1 at 500 degrees C with infinite selectivity (H2/N2). The membrane exhibited suitable performance when exposed to binary mixtures under various operating conditions. At 500 degrees C and 100 kPa, with the same concentration of impurity gases, the H2 permeance of the Pd88-Ni12 composite membrane was 3.33 x10(-7) mol m2 s1 Pa1 for the H2-Ar mixture, 3.12 x10(-7) mol m(2) s(1) Pa1 for the H-2-N2 mixture, 2.56 x10(-7) mol m(2) s(1) Pa-1 for the H-2-CO2 mixture, and 2.54 x10(-7) mol m2 s1 Pa1 for the H2-CO mixture. The effect of operating parameters and the amount of impurity concentration in the gas feed on the stage cut in binary gas mixtures was investigated. Increasing operating temperature and pressure enhanced the stage cut for all mixtures while increasing the impurity concentration in the gas feed led to a decrease in the stage cut, independent of operating conditions. The Pd88-Ni12 composite membrane indicated suitable long-time permeance stability for 150 h at a transmembrane pressure range of 100-300 kPa and 500 degrees C under an H2/N2 gas atmosphere. Finally, the cost investigation demonstrated that the Pd88-Ni12 composite membrane had a 38 % lower specific cost than the pure palladium composite membrane.

Automated summary

In this study, a Pd88-Ni12 composite membrane with considerable nickel content was prepared for the first time using the organic-inorganic activation method. The membrane exhibited high H2 permeance and infinite selectivity, making it suitable for various operating conditions and binary gas mixtures. Furthermore, the membrane showed good long-term stability and lower cost compared to pure palladium composite membranes.