Unbiased spectrophotometric method for estimating phenol or o-cresol in unknown water samples.
The generalised H-point standard addition method (GHPSAM) was applied to quantify phenol and o-cresol in waters and compared with other analytical approaches. The method is based on spectroscopic and kinetic measurement of the formation of derivatives with p-aminophenol and KIO(4) in presence of NaOH. First, pseudo-first order kinetic behaviour of the reaction products was demonstrated. The unbiased formation rate constants of phenol and o-cresol derivatives were calculated. The analytical figures of merit were determined using the GHPSAM as calibration method. Detection limits achieved were 0.2 microg L(-1) of phenol and 0.2 microg L(-1) of o-cresol using a preconcentration factor of 10. Styrene-divinyl benzene cartridges were used in the preconcentration step. Repeatability values were 3.7% for phenol and 2.0% for o-cresol; reproducibility values were 6.9% and 3.5%, respectively. Accurate and precise results were obtained when the method was applied to real samples of natural water.
Tortajada-Genaro
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LA
Departament de Química Analítica, Facultad de Química, Universitat de València, C/Dr Moliner 50, 46100 Burjassot, Spain.
Campíns-Falcó
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P
Bosch-Reig
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F
D003408:Cresols / Q000032:analysis*; D007700:Kinetics; D019800:Phenol / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D003408:Cresols; D014874:Water Pollutants, Chemical; D019800:Phenol; C034047:2-cresol