Supercritical CO2 (scCO2) is a phase of CO2 with very interesting physical properties. The CO2 is not strictly in the liquid or gas phase but somewhere in between: the supercritical phase. In this phase the CO2 exhibits both the properties of a gas (high diffusivity and low viscosity) and the properties of a liquid (high density), making scCO2 a very interesting extraction medium.
To obtain scCO2 high pressures and temperatures are required (at 73.8 bar and 32.1°C, the scCO2 phase is entered).
Centexbel has acquired a device to perform extractions up to 150°C and 700 bar. In addition, a co-solvent pump allows to add other - more conventional - solvents, to influence the solubility properties of scCO2.
This device allows Centexbel to perform research on the extraction of legacy additives from recycled plastics within the framework of the European H2020 projects CREAToR and REMADYL.
In addition to the research into the extraction of undesirable chemicals from recyclates, the interest in the use of scCO2 as a green solvent for textile dyeing has grown in recent years.
Acknowledgement
The equipment has been acquired in the framework of the EFRO GTI project.
