Extraction of Phenoxyacid Herbicides from House Dust Using Methanol/CO2 Mixtures

摘要: Current extraction techniques including conventional liquid−solid methods, supercritical fluid extraction, and accelerated solvent all suffer some potential drawbacks for the recovery of phenoxyacid herbicides from solid environmental matrices due to polarity, acidity, low volatility analytes. The use methanol/CO2 mixtures consisting 10−40 mol % methanol at both liquid conditions is investigated herein as an alternative. Four (dicamba, 2,4-D, 2,4,5-TP, 2,4,5-T) were extracted a house dust matrix. Highest yields (83−95%) obtained using 20/80 442 atm 100 or 150 °C. addition hexane directly sample followed by with CO2 offered simple method preextract extraneous matrix material. Subsequent extractions 0.1 M trimethylphenylammonium hydroxide in added yielded considerably lower results than those bin...