| Geothermal sour brines produced during gas extraction are of environmental concern in Alberta, as they can contain hydrogen sulfide up to 60 mM. Current means of treatment have limited efficiency or are simply not feasible economically. Therefore, the common method of disposal is re-injection into geologically stable sites. The goal of the present research was to use the affordable material coke for the electrolysis of sour brines. Electro-oxidation of sulfide ions occurred with a two-phase zero order reaction, which was attributed to sulfur deposition on the anode. The minor oxidative products were found to be elemental sulfur and sulfate. An organic sulfonate was determined to be the primary oxidative product, but an exact structure is yet to be proven. The electro-oxidation was found to have comparable energy efficiencies to boron-doped diamond (BDD), Ti/IrO2-Ta2O5 and graphite, making it a possible alternative for industrial scale treatment of geothermal sour brine. |
