Separation and concentration of beryllium by coprecipitation with hafnium hydroxide prior to determination by graphite furnace atomic absorption spectrometry
Hafnium hydroxide coprecipitates 0.01–0.2 µg of beryllium from 100–400 ml of sample solution at pH 6.0–10.5. The presence of hafnium quantitatively increases the atomic absorbance of beryllium by about 1.5 times, and the reproducibility of the measurement is improved. The calibration graph is linear for 0.4–8 ng ml–1 of beryllium. The interference induced by large amounts of aluminium can be eliminated by raising the pH of the solution to 13–13.5 with sodium hydroxide solution after the coprecipitation procedure has been carried out at about pH 9.5. Several other ions tested did not produce serious interference effects. This method is applicable to the determination of trace amounts of beryllium in water samples and in aluminium.