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The separation of H2S from natural gas, biogas, and coal gas is an essential process that requires large energy input and high capital costs. We propose a new sorption-based process, which can be coupled with the Claus desulfurization process to reduce sulfur emissions. This new process is based on a new sorbent material consisting of a specific composition of Cu, Mg, and Al oxides and exhibiting superior sulfur capacity (∼7.5 mmol/g) at process conditions compatible for integration with the Claus process. CuO is the active sorbent component, which during H2S uptake is converted to CuS and can be fully regenerated during cyclic operation. Al2O3 and small amounts of MgO are shown to be essential components that contribute to sorbent activity and stability.

Three biomass gasification-based hydrogen and power coproduction processes are modeled with Aspen Plus. Case 1 is the conventional biomass gasification coupled with a shift reactor, cases 2 and 3 involve integration of biomass gasification with iron-based and calcium-based chemical looping systems. The effects of important process parameters on the performance indicators such as hydrogen yield and efficiencies are evaluated by sensitivity analyses. These parameters include gasification temperature, molar ratios of steam to biomass in the gasifier, Fe 2 O 3 to syngas in the fuel reactor, Fe/FeO to steam in the steam reactor, CaO to CO, and steam to CO in the carbonator. The energy and exergy balance distributions for the above three cases are comprehensively discussed and compared. Furthermore, techno-economic assessments are performed to evaluate the three cases in terms of capital cost, operating cost, and leveled cost of energy.

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