A carbon molecular sieve membrane-based reactive separation process for pre-combustion CO 2 capture

Cao, Mingyuan; Zhao, Linghao; Xu, Dongwan; Ciora, Richard; Liu, Paul K.T.; Manousiouthakis, Vasilios I.; Tsotsis, Theodore T.

doi:10.1016/j.memsci.2020.118028

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A carbon molecular sieve membrane-based reactive separation process for pre-combustion CO 2 capture

Cao, Mingyuan·Zhao, Linghao·Xu, Dongwan·Ciora, Richard·Liu, Paul K.T.·Manousiouthakis, Vasilios I.·Tsotsis, Theodore T.

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Abstract

In this study, we discuss a hybrid system combining a membrane reactor (MR) and an adsorptive reactor (AR), with the MR's reject stream serving as the AR's feed. We apply this system for the water gas shift (WGS) reaction for H 2 generation and simultaneous CO 2 capture in the context of the Integrated Gas Combined Cycle (IGCC) process for power generation from coal and biomass. This MR-AR system attains a high conversion exceeding equilibrium, produces a pure H 2 product for power generation, and delivers a high-pressure CO 2 stream ready for sequestration. Specifically, in our study we use carbon molecular sieve membranes (CMSMs) and a commercial sour-shift WGS catalyst. Lab experiments were carried-out to determine the membrane characteristics, and the MR performance under IGCC-relevant conditions, i.e., for temperatures up to 250 °C and pressures up to 25 bar, employing a model coal gasifier syngas. The CMSM and the catalyst have displayed robust and stable performance during a long-term run (~750 h of syngas exposure). We evaluated the MR-AR system in multi-cycle runs and it has demonstrated superior performance to that of a conventional packed-bed reactor, producing a high-purity H 2 product directly useable in a turbine for power generation. We conclude from the study, that the CMSM-based MR-AR system is a good candidate technology for environmentally-benign power generation. We are currently constructing a pilot-scale system for field demonstration of the technology.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY adsorptive reactor carbon molecular sieve membrane membrane reactor water gas shift reaction

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Cao, Mingyuan, Zhao, Linghao, Xu, Dongwan, Ciora, Richard, Liu, Paul K.T., Manousiouthakis, Vasilios I., Tsotsis, Theodore T.. 2020-03-20. A carbon molecular sieve membrane-based reactive separation process for pre-combustion CO 2 capture. https://doi.org/10.1016/j.memsci.2020.118028

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