Abstract: A method and system for capturing H.sub.2 S from hot gas streams such as from a coal or other fuel gasifier are disclosed. Zinc or zinc oxide precursors in gas, liquid, or fine powder form are injected into the hot duct work of coal gasifier exit after fly ash has been removed to react with H.sub.2 S gas. In addition to ZnO sulfidation, a portion of the Zn-based reagents converted to the vapor state in the reducing fuel gas environment, reacts with H.sub.2 S and forms fine ZnS particles that are then collected on a high efficiency, high temperature filter. Periodically, the filter is backflushed, and spent sorbent is collected in a hopper, removed for regeneration, and returned to the injection system.

Abstract: A catalyst solution comprising one or more compounds of a metal catalyst and an organic solvent selected from the group consisting of a glycol derivative, an alkyl pyrrolidone, and an alkoxy ethyl ether, wherein no additional chloride-containing compounds are added to the solution. The metal can be selected from the group consisting of platinum, rhenium and rhodium. The compounds can be selected from the group consisting of H.sub.2 PtCl.sub.6.6H.sub.2 O, Re.sub.2 (CO).sub.10, Re.sub.2 O.sub.7, LiReO.sub.4 and RhCl.sub.3.4H.sub.2 O. The catalytic solutions are useful in conversion of pollutants from automotive engines and the like. In a particularly preferred embodiment, the solution contains three metals: platinum, rhenium, and rhodium.