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 wi th Eriochrome Cyanine R in the presence of ethylenediaminetetraacetic acid to give a highly absorbent complex, which is fixed on a dextran-t ype 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 s tandard deviation is 2.3%. The detection limit of the 1000 ml sample m ethod is 6 ng l-1 for 0.030 g of anion-exchange gel. The sensitivity c an be enhanced by increasing the sample volume. The method has been ap plied to the determination of beryllium in tap and natural waters.