A process for controlling H/sub 2/S emissions at geothermal power plants was evaluated in laboratory scale equipment and by process engineering analysis. The process is based on scrubbing geothermal steam with a metal salt solution to selectively remove and precipitate the contained H/sub 2/S. The metal sulfide is roasted or oxygen/acid leached to regenerate the metal salt, and sulfur is rejected from the system as elemental sulfur or as sulfate. Up to 95 percent removal of H/sub 2/S from simulated geothermal steams was obtained in a 2'' diameter scrubbing column packed with 3 feet of 5/8'' Flexirings by use of a recirculating slurry of copper sulfate/copper sulfide. Information is included on the chemistry, thermodynamics, kinetics and process control aspects of the process, scrubber system design, operation, and corrosion, and design proposals and cost estimates for a H/sub 2/S removal system. (LCL)