A method for co-processing H2S and CO2 in an electrolyzer includes feeding a first gas stream having H2S to an anode and feeding a second gas stream having CO2 to a cathode. The H2S is split into hydrogen and elemental sulfur. The hydrogen is transferred from the anode to the cathode, and the CO2 is hydrogenated with the transferred hydrogen. A method for producing electricity in a fuel cell includes feeding a first gas stream having H2S and CO to an anode, and feeding a second gas stream having oxygen to a cathode. The H2S and CO forms hydrogen and carbonyl sulfide. The hydrogen is transferred from the anode to the cathode. The transferred hydrogen is oxidized with the oxygen of the second gas stream, and electricity formed from the oxidation is collected.