Temperature effect on extraction and purification of used motor oil by supercritical carbon dioxide

摘要

Supercritical carbon dioxide (SC-CO2) was used for the extraction of used motor oil (UMO) from two types of contaminated sand (sieved and not sieved) at 70-80 degrees C and 35-65 MPa. The presence of fine sand in Sand 1 contributed to the increase of UMO recovery, decrease of outgassing losses and better purification of extracted UMO samples. All samples extracted at 70 degrees C from both sands were clean from engine wear residues and transparent while most of the samples extracted at 80 degrees C were black.