Acid dissolution of soils and rocks for the determination of boron by inductively coupled plasma atomic emission spectrometry

Abstract

The boron concentration in rocks, soils and standard reference materials was determined using hydrofluoric acid-aqua regia dissolution followed by inductively coupled plasma atomic emission spectrometry (ICP-AES) using the B I 249.773-nm line, corrected for spectral interference by iron. An excess of fluoride was complexed with aluminium to release boron from the stable fluoroborate ion and to protect the borosilicate and quartz components of the instrument. Boron was not lost by volatilisation during volume reduction.

Soil and rock boron values determined using the recommended dissolution procedures were comparable to those obtained using the accepted sodium carbonate fusion procedure and by d.c. arc emission spectrophotometry, and those for standard reference materials showed good agreement and precision with the literature values.