RAPID MICROWAVE-ASSISTED HYDROLYSIS OF FORMETANATE

A fast microwave-assisted hydrolysis procedure has been developed for the derivatization of formetanate previously to the flow-injection spe ctrophotometric determination of m-aminophenol by reaction with p-amin ophenol. Formetanate is quantitatively hydrolyzed with 0.1 M NaOH in 1 50 s using a closed polytetrafluoroethylene reactor with 115 ml intern al volume and a radiation power of 390 W. The above procedure has been applied, as a previous step, for the flow-injection spectrophotometri c determination of formetanate in spiked water samples and accurate an d precise results have been found. The method permits to obtain a limi t of detection of 0.025 mg l-1 of formetanate. The relative standard d eviation of five independent analyses of a sample containing 6 mg l-1 formetanate was 0.5%.