The development of supercritical fluids as solvents may help the chemicals industry meet environmental legislation and add momentum to its drive towards high-value, speciality products, Nottingham University researchers believe.
A supercritical fluid can be created by compressing a liquid/vapour system until the boundary between liquid and vapour disappears. In this state it exhibits properties of both gases and liquids, including the ability to disolve solids.
Paul Hamley, a technology transfer scientist at Nottingham University, said using non-toxic carbon dioxide as a solvent can cut the need for hazardous organic solvents and allows the use of smaller plant.
One industry insider said such processes could help save the UK chemicals industry at a time when bulk chemical production is shifting to emerging economies.
‘The UK industry’s future is likely to be in speciality and high-performance chemicals, and in high value-added products, with innovation being the key to success,’ he said. ‘Supercritical fluids are more relevant to these areas than to bulk chemical manufacture.’
‘Capital costs for supercritical fluids are similar to conventional processes,’ he added. ‘Vessel costs are greater because of higher pressures, but the vessel needed is smaller.’