Silica-PEI solid adsorbent looping technology at pilot scale

CO2 capture and storage (CCS) from large point anthropogenic sources, including coal and natural gas power plant and industrial processes is recognised to be one of the most effective measures to the European Union’s commitment to reach climate neutrality by 2050 and mitigate against global warming staying within 1.5 oC of pre-industrial levels during the remainder of the 21st century.  Post-combustion CO2 capture (PCC) will play a key role since it can be retrofitted and adapted to existing power plant and industrial processes.  Though amine scrubbing is the most mature technology, it has limitations resulting in relatively high capture costs and catalysing the development of alternative or second-generation technologies.  Solid adsorbents show considerable promise as such a technology, but are at a relatively early stage of development and have not been investigated extensively at pilot-scale and demonstration scale.

Silica-polyethylenimine (PEI) is a leading candidate amongst strongly basic adsorbents for both PCC and direct air capture.

What are we doing?

Initial analysis indicates that lifetimes approaching 12 months will be required for silica-PEI, assuming conservative performance parameters in terms of dynamic adsorption capacity and heat recovery.  Therefore, the overall aim of the proposed two-year research programme is to demonstrate that such lifetimes through optimising silica-PEI composition and SALT can achieve lower capture costs through maximising CO2 adsorption capacity.  Further, recovering the silica from spent adsorbent and converting the PEI to chemical feedstocks will be explored.  The findings will provide a basis of comparison with other technologies, including advanced amines and oxyfuel combustion where the focus will be on the cement industry.

This project will enable SALT to be bench marked in relation to amine scrubbing and oxyfuel combustion for both natural gas CCGT power plants and cement/lime production and provide the platform for taking silica-PEI SALT to full demonstrations at TRL 6-8.