Electrothermal Atomic Absorption Spectrometric Determination of Germanium by Coprecipitation with Hafnium Hydroxide

Various trace amounts of germanium in water were concentrated by the Coprecipitation technique with hafnium hydroxide, and determined by graphite furnace atomic absorption spectrometry. At pH 7.5-10.5, hafnium hydroxide coprecipitates almost completely 0.3-10μg of germanium from pure solution (less than 200ml) and more than 80% of germanium from natural waters (less than 200ml). The atomic absorbance of germanium is increased about 6 times by the presence of hafnium. The calibration curve is linear from 12 to 400ng ml-1 of germanium. The detection limit (signal/noise=2) was 0.3ng ml-1 of germanium in 200ml of the initial pure solution. This method was successfully applied to the determination of germanium in spring water, using the standard addition method.