This article explores the possibility of utilising supercritical CO₂ obtained from carbon capture and storage (CCS) as a solvent and examines the hydrogenation of isophorone to 3,3,5-trimethylcyclohexanone using supercritical CO₂ with added N₂, CO or H₂O to emulate the contaminants expected in CO₂ from CCS. None of the impurities appear to cause insuperable problems in the hydrogenation of isophorone when present at concentrations likely to be found in CO₂ from CCS. N₂ introduces modest changes in phase behaviour at some pressures, while CO and H₂O reduce the activity of the catalyst. However, the activity can be largely regained by increasing the reaction temperature.