The few impurities in carbon dioxide captured from burning coal and natural gas should not preclude using the gas to generate supercritical CO2 for use as an industrial solvent, according to a team of European chemists (Green Chem., DOI: 10.1039/c1gc15503b). Although successfully used to replace organic solvents in a variety of lab-scale reactions, only a few supercritical CO2 processes have been commercialized because of the high cost of pressurizing CO2. Carbon capture and storage, which is being implemented to cut CO2 emissions, now provides a continuous, cost-effective source of pressurized CO2. But how impurities in captured CO2 might affect chemical processes presented a question. Martyn Poliakoff, Michael W. George, and Trevor C. Drage of the University of Nottingham, in England, and coworkers have answered it by testing a discontinued commercial process—hydrogenation of isophorone to make trimethylcyclohexanone—in supercritical CO2 laced with N2, CO, or H2O to simulate probable contaminants. They found that N2 introduces modest phase changes and that CO and H2O reduce catalyst activity, but that activity can be maintained by increasing the reaction temperature. None of the impurities cause insuperable problems, the researchers note, and they believe their findings could help reboot industrial supercritical CO2 reactions.