Spectrometry

A solid phase derivative extraction method using acetic anhydride was developed for the determination of chlorophenols and alkylphenols in water and fruit juice by gas chromatography-mass spectrometry (GC-MS). The quantitative extraction was performed by passing 100mL of sample prepared in 0.1molL(-1) sodium hydroxide through a column packed with 500mg of a strong anion-exchange resin at a flow rate of 0.75mL min(-1). The retained phenols were quantitatively derivatized in the column by the introduction of 0.25mL of acetic anhydride. The derivatized phenols were eluted with 3.0mL of hexane and the effluent was dried under nitrogen. The final volume was diluted to fifty microliters with hexane and analyzed by GC-MS. Under the optimum conditions, preconcentration factors of 2000, limits of detection between 0.005 and 1.796 mu gL(-1), and relative standard deviations of 2.1% to 6.7% were obtained. The method was successfully applied to wastewater and fruit juice and the recoveries of phenols were between 76% and 111%