Abstract
A spectrophotometric method has been studied for a simple and accurate determination of trace levels of boron in high purity graphite. An appropriate weight (less than 2 g) of sample was taken in a silica dish mixed with calcium hydroxide prepared from pure calcium, and ashed in a muffle furnace. The residue was dissolved in 10% acetic acid. After the addition of glycerol, the solution was evaporated to dryness. To the residue were added curcumin-acetic acid and sulfuric-acetic acid. The mixture was diluted with ethanol, and the absorbance at 555 nm was measured. The relative standard deviation was 3% for samples with 2 μg-1 levels of boron. The results on CRMs JAERI-G5 and G6 were in good agreement with the certified values.
