Evaluation of Sorbents for High Temperature In Situ Desulfurization of Biomass-Derived Syngas

In a preparative study, the use of different sorbent materials for in situ desulfurization of biomass derived synthesis gas is evaluated. Results of phase equilibrium calculations using FactSage version 6.4 for the H 2 S equilibrium concentration with a variation of different parameters are compared to values for the residual H 2 S content found in literature. The focus is strictly set on a high temperature, high steam application for biomass-derived syngas conditions. Possible synergistic effects between different sorbent components and deviations from simulated results are discussed subsequently. The use of copper-based sorbent material turns out to be promising due to a predicted positive impact of high steam conditions for sorption equilibria. Results for the implementation of a CaO–BaO mixed phase sorbent are confirmed, qualifying this material combination as a promising candidate for in situ application. Equilibrium calculations predict a desulfurization of syngas to a sulfur level of 2.1 ppm v H 2 S at a steam content of about 40 vol % and 820 °C which is sufficient for further catalytic gas processing applications.