Palladium based sorbents for high temperature arsine removal from fuel gas

The use of Pd-based sorbents for high temperature removal of AsH3 from gasified coal was investigated using a simulated gas feed. A sorbent consisting of 5 wt% Pd on alumina beads has been tested for AsH3 removal from synthetic fuel gas (CO, CO2, H2) at 204 and 288 °C. Arsenic uptake was found to be essentially linear with exposure time and considerably higher than that for unpromoted alumina beads. Arsenic loadings in excess of 7 wt% were achieved, though the sorbent is unlikely to be saturated at this loading. As the arsenic loading on the sorbent increased a PdAs2 phase was identified in the XRD pattern. The adsorption of arsine on palladium has potential implications for catalysts, electrodes, and membranes for the separation of hydrogen from fuel gas.