Solid oxide electrochemical systems were evaluated for the reduction of NO{sub x} and SO{sub x} in a coal-fired turbine exhaust. Yttria stabilized ceria and zirconia were studied as electrolytes over the temperature range 1,600---2,500{degrees}F. Yttria stabilized zirconia was the most useful electrolyte and two high surface area geometries were developed. Platinum was the electrode material; less noble metals were investigated, as well as conductive minerals, but replacement of the platinum was unsuccessful. Transition metal oxides were applied as electrocatalysts. With vanadium and tungsten coatings, sulfur dioxide concentrations were reduced 20 to 50% using an initial SO{sub 2} concentration of approximately 2,500 ppm. Electrical efficiencies for the decomposition of SO{sub 2} in the oxygen containing environment (1--4%) were approximately 5%. Though electrocatalysts did allow for the destruction of NO ({approximately}400 ppM) in an oxygen containing atmosphere, the efficiencies were only 1%. Limited investigation of perovskites demonstrated their potential as electrocatalysts in these extreme conditions. 3 refs., 26 figs., 12 tabs.