High-pressure homogenisation prior to slurry introduction electrothermal atomic absorption spectrometry for metal determinations in wood pulps

High-pressure homogenisation of softwood pulp fibres was evaluated as a sam ple preparation procedure prior to Cu, Fe and Mn determination by electroth ermal atomic absorption spectrometry. Although homogenisation in tetramethy lammonium hydroxide proved to be unsuitable, fibres that had been pre-swoll en with aqueous zinc chloride were readily homogenized to result in slurrie s that provided repeatable estimates of analyte concentrations, which were analogous to estimates obtained from solutions prepared by conventional or microwave-assisted digestion with strong oxidants. The release of analytes into the aqueous phase however was incomplete, even with the addition of ED TA or DTPA complexing reagents to the crude fibre suspension or cellulase p lus xylanase-assisted digestions of the suspension post-homogenisation. The advantages of this procedure for sample preparation included time saving a nd decreased operator intervention. Sample preparation was completed in 5 m in.