Project description
Investigating CO2 capture on porous silica adsorbents
Reaching a record high of 32.5 gigatonnes in 2017, global CO2 emissions from fossil fuel combustion continue to increase. Adsorption is considered a viable technology to reduce CO2 emissions. Because of its lower regeneration cost, amine-modified porous silica (AMPS) is the most promising CO2-adsorbent material for replacing the decades-old liquid amine-scrubbing technology. However, a molecular-scale understanding of the CO2-AMPS adsorption process remains elusive, hindering progress in the design of improved sorbents. The EU-funded NMR4CO2 project addresses this need, using – for the first time – state-of-the-art surface-enhanced nuclear magnetic resonance to study the chemistry of acidic gases (mainly CO2) adsorbed on AMPS and of gas-solid interfaces using simulated industrial gas mixtures.
Objective
Reaching a historic high of 3Reaching a historic high of 32.5 gigatonnes in 2017, global carbon dioxide emissions from fossil fuels combustion continue to increase. CO2 removal technologies are part of the solution to tackle this crucial environmental challenge. Because of their lower regeneration cost, amine-modified porous silicas (AMPS) are the most promising CO2-adsorbents for replacing the decades-old liquid amine scrubbing technology. AMPS are “moisture-tolerant” and selectively chemisorb CO2 from low-concentration mixtures, important features for operating under large-point CO2 emission source conditions.
The nature of CO2 species formed on AMPS surfaces determines the gas adsorption capacity/kinetics, selectivity, stability, and regenerability. However, a molecular-scale understanding of the CO2-AMPS adsorption process remains elusive, hindering our ability to design improved sorbents. NMR4CO2 aims to fill in this gap, engaging for the first time state-of-the-art surface-enhanced ex- and in-situ solid-state NMR (SSNMR) to study the chemistry of acidic gases (mainly CO2) adsorbed on AMPS, and the gas-solid interfaces, using simulated industrial gas mixtures. The project combines the expertise of spectroscopists, chemists, and engineers to tackle these challenges.
NMR4CO2 encompasses the design of novel SSNMR methods to study the kinetically- and thermodynamically-driven CO2-AMPS adsorption process, comprising in-situ flow NMR, dynamic nuclear polarization NMR, and isotopically-labeled gas mixtures. Important outcomes include: i) identification of competing CO2 chemisorption pathways; ii) effect on CO2 speciation of textural properties, amine type, inter-amine spacing, and amine-support cooperative effects; iii) real-time monitoring of acid gas speciation in multiple adsorption/desorption cycles; iv) identification of sorbent deactivation species; v) effect of pressure on CO2 speciation and vi) improvement of AMPS sorbent properties by synthetic modification.
Fields of science
Programme(s)
Funding Scheme
ERC-COG - Consolidator GrantHost institution
3810-193 Aveiro
Portugal