'Molecular Basket' Sorbents for Separation of CO_2 and H_2S from Various Gas Streams

摘要

A new generation of "molecular basket" sorbents (MBS) has been developed by the optimum combination of the nanoporous material and CO_2/H_2S-philic polymer sorbent to increase the accessible sorption sites for CO_2 capture from flue gas (Postdecarbonization), and for CO_2 and H_2S separation from the reduced gases, such as synthesis gas, reformate (Predecarbonization), natural gas, coal/biomass gasification gas, and biogas. The sorption capacity of 140 mg of CO_2/g of sorb was achieved at 15 kPa CO_2 partial pressure, which shows superior performance in comparison with other known sorbents. In addition, an exceptional dependence of MBS sorption performance on temperature for CO_2 and H_2S was found and discussed at a molecular level via the computational chemistry approach. On the basis of the fundamental understanding of MBS sorption characteristics, an innovative sorption process was proposed and demonstrated at the laboratory scale for removing and recovering CO_2 and H_2S, respectively, from a model gas. The present study provides a new approach for development of the novel CO_2/H_2S sorbents and may have a major impact on the advance of science and technology for CO_2/H_2S capture and separation from various gases.