COMPLEXOMETRIC DETERMINATION OF MERCURY(II) IN WATERS BY SPECTROPHOTOMETRY OF ITS DITHIZONE COMPLEX

This paper presents a new method for the determination of Hg(II) in wa ters, using ''indirect'' spectrophotometric measurements of the Hg(II) dithizone complex. The reagent is a mixture of dithizone, CDTA (1,2-c yclohexylene-dinitrilo-tetraacetic acid), thiourea, ethylic alcohol an d glycine. Sensitivity and working range are 0.4 mug.l-1 and 2-100 mug .l-1, respectively. A comparison of the results with those of the cold -vapor atomic absorption spectrometry shows a good correlation for dif ferent samples revealing only small interferences. The new method is w ell suited for on-line measurements, easy to run and has low cost equi pment.