FLOW-INJECTION ANALYSIS FOR BERYLLIUM DETERMINATION WITH CHROME AZUROL-S AS CHROMOGENIC AGENT

A flow injection analysis system which employs a visible absorption detector is used for the determination of beryllium. Be(II) ions are detected by means of a complexation reaction between Be(II) and chrome azurol s as the chomogenic reagent. The reaction forms a stable 1:1 complex which appears dark red-violet. The optimum conditions for the determination are pH 4.15, 35% chrome azurol s, 3% buffer, 62% HCI and 1,3-phenylenediamine, flow rate of 1.0 mL/min, 'and wavelength at 570 nm. A concentration limit of 0.1 mug/mL (or 2 ng in 25 muL of a sample injected) of Be(II) can be detected, and the linear dynamic range extends to 100 mug/mL. Some interference limits are established in the presence of EDTA and thiosulfate which are used as masking agents.