Purification of used frying oil by supercritical carbon dioxide extraction

摘要

Supercritical fluid extraction (SFE) was used for the purification of used frying oil at different temperatrues (40 and 60 deg C) and pressures (150, 225 and 300 bar). The calculated solbuilities of the oil ranged from 0.3×10~(-3) to 7.4×10~(-3) g oil/g CO_2 depending on the extraction conditions. The solubility and the selectivity of triglycerides (TG) were between those of the low moleculr weight compounds (LMWC) and the polymrs. The calculated relative separation effficiency (R) of low molecular weight compounds (LMWC) from TG was highest under the low pressure and high temperature extraction conditions, but the extraction rate was miimal under this condition.