Biogas desulfurization with regenerable polymeric adsorbent for renewable electric energy production

To improve the standard of living worldwide, it is necessary to increase the availability of energy, as the quality of life and energy consumption are directly connected. Thus, electric utility companies have the challenges of increasing the availability of electricity and reducing emissions for gasses that contribute to global warming. Biodigestion of animal manure is a source of biogas, which can be used as a sustainable fuel in electric generators. Electricity producers can use biogas produced on rural properties and produce sustainable electricity that would work on a smart grid with other forms of sustainable energy. Biogas contains hydrogen sulfide (H2S) in a range from 0.2 to 1.0% (vol/vol) that should be removed to avoid generator corrosion and environmental impact after its combustion. Adsorption is a feasible process to separate a dilute compound from a stream. We tested a commercial polymeric adsorbent (Macronet (TM) MN200), whose specific adsorption was in the range from 0.95 to 1.09 mg of H2S per gram of dried adsorbent when working in a packed bed system with biogas. The adsorbent was completely regenerated three times in batch experiments and once in a continuous experiment by heating the saturated material at 130 degrees C. The H2S adsorption kinetics was successfully modeled by the Thomas and Yoon-Nelson equations. Our study shows that a packed bed with the tested adsorbent is a feasible solution for the desulfurization of biogas used in electricity production, which is relevant for converting biogas into a sustainable form of electricity.