Electrochemical oxidation of sulfide ions in synthetic sour brines using Ebonex electrodes
A considerable number of gas wells in Alberta contain sour gas accompanied with sour brines. Natural gas wells often require the injection of steam or hot water for extraction. The resulting extraction is accompanied by a contaminated aqueous solution known as geothermal brine, which may contains a variety of organic and inorganic species. Hydrogen sulfide is one of the main problems encountered in the gas wells. The costs of the transportation and re-injection of sour brines are highly expensive for the oil and gas companies. Current means of treatment, such as biological and chemical would increase the costs of the treatment as it requires using pressurized tanks during the transportation to avoid volatilization of sulfide ions. Electrochemistry can offer an environmentally friendly treatment method for remediation of sulfide ions. Because of cost and stability considerations, Ebonex® was used as an electrode for oxidation of sulfide ions to mainly sulfate. This was done using different experimental setup, matrixes and currents. By using two Ebonex® system with polarity reversal, Ebonex® could maintain its activity. Studying the surface also showed some modification as a result of the anodic polarization during electrolysis process.