Hydrogen sulfide is met in different natural sources, like the deep waters of the Black Sea, some closed water ponds, natural springs of mineral water, etc. It is also present in some effluents at oil processing by de-sulfurization. A straightforward method to remove hydrogen sulfide is to convert it into sulfate in sulfide-driven fuel cells (SDFC). This process is accompanied by the generation of energy directly as electricity.
A problem of this application is the big variety of sulfur compounds of different valences leading to incomplete sulfide conversion and lower energy yield. This problem must be overcome by the use of selective catalysts able to promote the complete conversion of sulfide to sulfate.
The present work comprises the results of the use of different compounds of metal ions, namely zirconia, cobalt spinel, zinc oxide. The study on their catalytic activity shows the advantages of zinc oxide embedded in pyrolysed carbon source for the complete conversion of sulfide to sulfate. Lab-scale experiments show that the fuel cell application is direct method for hydrogen sulfide removal either for environmental or energy benefits.
This work was supported by the program Eplus, Ministry of Education and Science, Republic of Bulgaria.
- Knowledge about fuel cells.
- Catalytic properties of heavy metals for sulfide oxidation.
- The combination of environmental issue and energy production could be applied elsewhere.