High-temperature separation of H₂S from producer gas produced of biomass gasification by artificially prepared sorbents

Commercial technologies are available to clean gasification hydrocarbon gases to the stringent levels of contaminants. However, new cheaper technologies are needed for stringent gas cleaning duty for producer gas production from biomass at high temperatures for use in fuel cells. This article describes the thermodynamics calculations aimed to estimate the suitability of various prepared sorbents on the basis of metal oxides (CaO, MnO, FeO, Fe₂O₃, ZnO and ZnFe₂O₄) to clean hydrogen sulphide from the producer gas at elevated gas temperatures and experimental verification of the function of prepared sorbents during specific conditions such as temperature and raw gas composition. Our prepared sorbents on the basis of zinc and copper oxides prove high sorption capacities for selective sorption of H₂S. These sorbents can be with big advantage used in the industry for removal of H₂S from biogas at high temperature. Output gas contains only low concentrations of H₂S and can be then used for high-temperature fuel cells to produce electricity.