Sunshine superabsorbent could reduce energy demand of CCS

Developed by researchers in Australia, the material could reduce the amount of energy needed to move CO₂ captured from fossil fuel burning into a storage facility.
The material, synthesised by research leader Matthew Hill of the Australian research agency CSIRO and colleagues at Monash University in Melbourne, is a metal-organic framework or MOF, a class of highly porous materials already well-known for their ability to store gases. Made by joining together clusters of metal atoms with organic bridging molecules known as ligands, MOFs can have internal surface areas as high as 10,000m² — larger than the pitch at Wembley Stadium — per gramme.

This particular MOF is the first to be made photosensitive.

‘The MOFs are impregnated with light-responsive azobenzene molecules which react to UV light and trigger the release of CO₂,’ explained researcher Richelle Lyndon. ‘It is this reaction, and the material’s ability to bend and flex, which makes the material we have created so unique.’

Current CCS techniques tend to use ammonia-based liquids to absorb CO₂ from flue gas streams, which must then be heated to release the CO₂ into storage and regenerate the absorbent. This can consume up to 30 per cent of the production capacity of a power plant, and is a major contributor to the difficulty of making CCS cost-effective.