Four potential absorbents: zinc sulfate, nickel, coal ash leachate, and redox reagents, have been identified and evaluated. The ZnSO/sub 4/ absorbent had excellent H/sub 2/S removal capability, and will simultaneously absorb ammonia. However, regeneration of the ZnS has been incomplete, and is expected to be excessively slow. Nickel works best as Ni(OH)/sub 2/. H/sub 2/S removal efficiency is excellent, and regeneration capability is good. Because the absorbent is a slurry, some plugging of the absorption column was noted. The coal ash leachate was simulated with Fe(OH)/sub 3/. This has been found to be the poorest of the absorbents, although its H/sub 2/S absorption efficiency is adequate. Because the absorbent is derived from coal ash, regeneration is not an issue. The redox process has been evaluated in several modes: 2-stage absorption/regeneration with FeNaHEDTA redox reagent, direct oxidation with the redox reagent, and water only direct oxidation, the last of which was found to be unexpectedly effective. The major concern of the processes using the redox reagent is degradation of the organic HEDTA, which was measured and found to require careful control. The water only process, particularly with incorporation of an oxidation catalyst was found to be extremely attractive. Ammonia is simultaneously removed in all modes. Liquid to gas ratios are in the range of existing low temperature H/sub 2/S scrubbing processes. It has been determined that three of the four proposed absorbent processes are potentially attractive for mid-temperature (150 to 200/sup 0/C) H/sub 2/S scrubbing. Because of the potential simplicity of the process it has been decided to pursue the direct-oxidation mode of the Redox process, with and without the redox reagent. It should be noted that the Ni(OH)/sub 2/ and coal ash leachate processes have also shown good promise.