DETERMINATION OF BORON IN WATERS AND WATE R-EXTRACTS OF WASTES BY MOLECULAR AND ATOMIC-ABSORPTION SPECTROMETRY AFTER PRELIMINARY BORON SEPARATION BY EXTRACTING THE COMPLEX WITH 2-ETHYLHEXANE-1,3-DIOL

Two methods for the determination of boron have been developed and tes ted based on the separation and preconcentration of boron by extractio n from an acidified aqueous solution into chloroform solution of 2-eth ylhexane-1,3-diol (EHD) and reextraction into aqueous reextraction sod ium hydroxide, followed by spectrophotometric measurement with curcumi ne at 543 nm or AAS with a nitrous oxide-acetylene flame at 249.8 nm. The limits of determination (3s criterion) are 0.002 and 0.1 mg/1 for the former and latter method, respectively. The proposed methods were compared with the well-known spectrophotometric method employing azome thine-H. The sensitivities of the methods are similar (the limit of de termination for the azomethine-H method is 0.02 mg/l), but the newly p roposed methods exhibit a better reliability and are widely applicable to the determination of total boron in all types of water and water e xtracts.