CO2 dry cleaning: Acoustic cavitation and other mechanisms to induce mechanical action

High pressure carbon dioxide (CO2) is a potential solvent for textile dry cleaning. However, the particulate soil (e.g. clay, sand) removal in CO2 is generally insufficient. Since cavitation has been proven to be beneficial in other CO2 cleaning applications, this study aims to investigate the possibility of improving the performance of CO2 textile dry cleaning by using ultrasound or other mechanisms to induce the mechanical action such as bubble spray and jet spray. In the experiments, several types of textiles soiled with a mixture of motor oil and soot were cleaned using 1 Land 90 L CO2 dry cleaning set-ups. Using either ultrasound, stirring, liquid spray or bubble spray does not give a significant improvement on particulate soil removal from textile. It was also found that the additional use of ClipCOO detergent does not give a significant improvement on particulate soil removal either. The cleaning performance of CO2 is 50% lower than that of PER and thus another method to increase the particulate soil removal in CO2 textile dry cleaning still needs to be developed.