Complexation-supercritical carbon dioxide extraction of copper ions from solid matrices with thenoyltrifluoroacetone and modifiers

The method of chelant thenoyltrifluoroacetone complex copper ions combined with supercritical fluid extraction (SFE) was used to extract Cu2+ from solid matrices. The influences of pressure, temperature, and total volume of CO2 used in the extraction on the recovery of Cu2+ were studied systematically in the 40-100 degreesC range at pressures up to 35 MPa. In order to improve recovery of Cu2+, three modifiers of different polarities (methanol, dichloromethane, and toluene) were tested, respectively. All the modifiers can improve the efficiency of the extraction, with methanol being the most efficient. Most of the Cu2+ (recovery = 97.3%, R. S. D = 2.88, n = 4) can be recovered from the solid matrices at suitable conditions.