“…Various solvents have been proposed for desorption of compounds from PUF: acetone, 11,107,110,117,152 hexane, 107,133,134,153 methanol, 117 an acetone ± hexane mixture, 133 diethyl ether and petroleum ether. 121 Solvent desorption is carried out in the Sohxlet apparatus for 18 ± 24 h. 107, 113, 115, 116, 118, 130, 132 ± 134, 149 In some cases, samples are treated with ultrasound to intensify the process.…”