In this paper; three methods for the detection of hexenuronic acid (HexA) in unbleached nan bleached softwood krafts pulps were compared The methods were based on total enzymatic hydrolysis of pulp combined,with high-performance anion-exchange chromatography of the liberated HexA-substituted xylo-oligosaccharides (the VTT method), selective acid hydrolysis of pup combined with UV spectroscopy of the hydrolysis products (the HUT method), and selective mercuric acetate hydrolysis of pulp combined,with colorimetric determination of the hydrolysis products (the KTH method). The results obtained by the three methods correlated well with each other. The highest values were obtained with the KTH method and the values obtained with the VTT mid HUT methods were 90-95% and 75-86% of the the KTH values, respectively. None of the methods was clearly superior to the other two in the analysis of HexA. However, the VTT method allows simultaneous quantification of 4-O-methyliduronic acid and 4-O-methyliduronic acid along,with the analysis of HexA.
|Journal of Pulp and Paper Science
|Published - 1999
|MoE publication type
|A1 Journal article-refereed