Acid mine drainage wastewater photoelectrolysis for hydrogen fuel generation: Preliminary results

Acid mine drainage (AMD) occurs when sulfide composite materials are exposed to oxygen gas, water, and microorganisms present in the environment. An alternative for the treatment of this residual water is the generation of hydrogen gas by electrolysis using a photovoltaic system. In this work, an electrolytic cell with 304 stainless steel electrodes was to form hydrogen gas. After 390 minutes of hydrogen generation, it was observed that the accumulated amount of H2 was 254 mL when PV panels were used as the current source. When using AMD, hydrogen generation was 5.5 times higher compared to that using the sulfuric acid solution under the same experimental conditions. The electrolyte AMD conductivity diminished from 3850 μS cm−1 to 2960 μS cm−1. The decrease in conductivity may be related to removal of metal ions from the solution by the formation of insoluble compounds. After 390 minutes of testing, electrolysis using a PV panel resulted in a 9-fold increase in the total solid content. The reduction of iron and manganese ions in AMD samples was approximately 60% and 10%, respectively. No decrease in sulfate concentration and low pH variation were observed.