Mo-Doped FeS Mediated H<sub>2</sub> Production from H<sub>2</sub>S via an In Situ Cyclic Sulfur Looping Scheme
Kalyani Jangam, Yu‐Yen Chen, Lang Qin, Liang‐Shih Fan
Abstract
Decomposition of H2S into sulfur and clean fuel H2 is an attractive process and requires a design concept with a maximum H2S conversion and a minimal energy consumption. Herein, we demonstrate a sulfur looping scheme in a one-reactor system using a low-cost and environmentally safe iron-based sulfur carrier. H2S decomposition is split into cyclic sulfidation and regeneration of sulfur carriers, which overcomes the inherent thermodynamic constraint, allowing in situ H2 generation. We experimentally obtained 24% higher sulfur uptake in 2% Mo-doped iron-based sulfur carriers compared with undoped sulfur carriers. The reaction mechanisms unveiled by the density functional theory indicate that surface hydrogen diffusion is the rate-determining step for sulfidation of the sulfur carrier. Compared with the undoped sulfur carrier, Mo dopant facilitates the surface hydrogen diffusion, thus promoting the overall H2S conversion. This work demonstrates a novel strategy for high-yielding H2S removal through low-percentage dopant modification sulfur carrier and provides new insights for an effective dopant screening strategy aiding the future carrier design.