The analyses were performed as shown in Fig. Water, deionized and purified with a Milli-Q® apparatus (Millipore), was used in the recovery study. The PCP standard (99.73%) was obtained from the Environmental Protection Agency (Triangle Park, NC). Acetic anhydride, anhydrous sodium sulfate and potassium carbonate were of analytical reagent grade (Merck). Operating conditions were as follows: injector temperature, 210 ☌ column oven temperature, 180 ☌ detector temperature, 300 ☌ and carrier gas (N 2) at 30 mL/min.Īll solvents used were of pesticide grade quality (Carlo Erba): n-hexane, and acetone. The signal from the ECD was monitored with a Varian 4290 Integrator. The method was used to determine PCP in drinking water samples from different cities of the State of São Paulo, Brazil.Ī Varian 3300 gas chromatograph equipped with a glass column (2 m x 2 mm id.) packed with 3% OV 210 on 80-100 mesh Chromosorb WHP, and a constant current 63Ni electron capture detector (ECD) was used for qualitative and quantitative analyses. 6, and involves: in situ acetylation of PCP with acetic anhydride in the presence of potassium carbonate, plus extraction by hexane, and analysis of the extract using gas-liquid chromatography with electron capture detection. This paper describes a modification of the method proposed by Lee et al. The advantages of the in situ derivatization eliminate the deficiencies of incomplete recovery of free PCP from water samples by solvent extraction 6 and permit derivatization and extraction in a single step. One involves the extraction of PCP from samples by solvents before the derivatization, while the other involves the direct derivatization of PCP in aqueous solution ( in situ derivatization). The analyses of PCP in water are done using two approaches. Thus, the derivatization of phenols prior to chromatography is often recommended 8. Although the derivatization methods require special pre-chromatographic treatment, the analysis of underivatized phenols by high resolution gas chromatography (HRGC) also has disadvantages. Many studies have been reported for derivatization of PCP in water, including acetylation with acetic anhydride leading to pentachlorophenyl acetate 6 or preparation of the pentachlorophenylmethyl ether derivative with diazomethane 7. Among these techniques, gas liquid chromatography with higher sensivity of the electron capture detector (ECD) allows the PCP determination at very low concentration levels 4-5,but requires a derivatization step before GC analysis. Several methods have been described to determine PCP by using various analytical techniques 1-4. Pentachlorophenol (PCP), a fungicide and insecticide used in wood treatment, agriculture, paper production, and the leather industry, has become a serious environmental concern because of its toxicity to fish and mammals. Keywords: pentachlorophenol, water, gas chromatography, in-situ derivatizatio The limit of detection of the method is 1 mg/L and recoveries averaged 78-108% for PCP acetate at levels of 2, 10 and 20 mg/L. ![]() The PCP derivative analysis was performed by gas-liquid chromatography with electron capture detection. In this study, an in situ derivatization and extraction method for the determination of pentachlorophenol (PCP) has been applied successfully in the analysis of water samples. O limite de detecção do método é de 1 mg/L e sua eficiência é demonstrada pelos valores médios de recuperação (78-108%) estudados em três níveis de fortificação (2 10 e 20 mg/L). O derivado acetilado de PCP é analisado por cromatografia a gás com detector por captura de elétrons. Este trabalho relata um método envolvendo derivação in situ e extração para determinação de resíduos de PCP em amostras de água.
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