DETERMINATION OF TRACE AMOUNTS OF BERYLLIUM IN WATER BY SOLID-PHASE SPECTROPHOTOMETRY

A method for the determination of trace amounts of beryllium has been developed, based on solid-phase spectrophotometry. Beryllium reacts with Eriochrome Cyanine R in the presence of ethylenediaminetetraacetic acid to give a highly absorbent complex, which is fixed on a dextran-type anion-exchange gel. The absorbance of the gel, at 580 and 750 nm, packed in a 1 mm cell, is measured directly. The calibration graph is linear over the concentration range 0.1-1.2 mug l-1 and the relative standard deviation is 2.3%. The detection limit of the 1000 ml sample method is 6 ng l-1 for 0.030 g of anion-exchange gel. The sensitivity can be enhanced by increasing the sample volume. The method has been applied to the determination of beryllium in tap and natural waters.