Preparation of thin and dense electroless-plated Pd membrane by controlling Pd deposition behavior

Abstract

Electroless Pd plating at different deposition temperatures was investigated to control Pd deposition behavior for preparing a much thinner Pd membrane to reduce Pd usage and achieve high hydrogen permeation flux. The deposition temperature directly influenced on the membrane thickness uniformity and defect formation. In our experimental condition, a thin Pd electroless-plated membrane with a thickness of 3 m could be prepared at 333 K using a formic acid bath. It was found that this membrane showed no leakage of helium and high H 2 permeation flux. The rate-limiting step of Pd deposition during the electroless plating must be one of the important factors for preparing the thinner Pd plating membrane with no pinholes.

Hydrogen separation from mixed gas (H2, N2) using Pd/Al2O3 membrane under forced unsteady state operations

“…The time lag for this experiment with a constant feed gas composition is approximately 7000 s and the average hydrogen recovery after reaching steady state conditions reached 19%. In the start-up period, the feed gas containing hydrogen commenced permeating from the retentate (shell) side into the permeate (tube) side by following the solution-diffusion mechanism [55,59]. At the beginning of the process, the driving force induced by the concentration difference between both sides was very high, leading to quick hydrogen permeation through the membrane wall.…”