Resin phase spectrophotometry of beryllium by an optical fiber and beryllon II

We have developed a resin phase spectrophotometric method to determine the amount of beryllium by detecting a change in absorbance of the resin phase. 8-Hydroxynaphthalene-3,6-disulphonic acid-(1-azo-2')-1',8'-dihydroxynaphthalene-3',6'-disulphonic acid tetrasodium salt (beryllon II) immobilized by a strong base anion-exchange resin on the end of a bifurcated optical fiber bundle was chosen as a material sensitive to beryllium. Experiments were made using a home-made optical fiber spectrophotometer. The properties of the resin phase proved to be good for continual use of 350 times during a month. The reaction order between immobilized beryllon II and beryllium in solution was determined by kinetic theory and experiments. This method was also used to determine the amount of beryllium in beryllium-copper alloy; the response was linear from 0.43 to 2.60 mug/ml at pH 12.5 and 676 nm. The effect of interfering ions on the determination of beryllium was studied at the same time.