Simulation and Validation of Hydrogen Production From Hydrogen Sulfide Pyrolysis

Pyrolysis of hydrogen sulfide has been studied for the treatment of hydrogen sulfide with simultaneous production of hydrogen and sulfur. This novel treatment method has been studied experimentally to provide fundamental information on the overall kinetic parameters. Numerical simulation of thermal pyrolysis of hydrogen sulfide is studied and the results obtained from the modified detailed chemical reaction mechanism are validated with the experimental data. The simulation results agreed favorably well with the experimental data for all examined temperatures up to 1473K. The thermal pyrolysis of hydrogen sulfide has been studied at residence times of 0.4 to 1.5 seconds and at temperatures of 1273–1473K. Experiments and simulations were also conducted using hydrogen sulfide diluted with 95% nitrogen using a heated quartz plug flow reactor to avoid any catalytic effects and excessive build of sulfur during experimentation. Numerically plug flow type reactor model was used to simulate the hydrogen sulfide thermal pyrolysis. The available mechanism in the literature provided poor match with the experimental data at temperatures higher than 1273 K. A modified mechanism is proposed and validated with our experimental data. Both simulations and experimental results showed increased conversion of H₂S to hydrogen at increased temperatures. The increase in temperature reduced the residence time required to reach a steady asymptotic equilibrium value. Based on the qualitative agreement between simulations and experimental data under the investigated conditions, the reaction pathways as well as the most dominant reactions on hydrogen sulfide thermal pyrolysis are also presented. These results assist our efforts in the development of new technologies for hydrogen sulfide treatment.