Supercritical fluid extraction of wood pulp with analysis by capillary gaschromatography-mass spectrometry

A supercritical fluid (SF) extraction method for the analysis of extractabl e material in eight hardwood and softwood pulp samples was investigated. Wh ile the majority of the extractable material in a Soxhlet extract with meth ylene chloride was determined to be fatty acids, the presence of their corr esponding methyl esters along with fatty acids was noted in the SF extract. Grinding the samples increased extractable fatty acid methyl esters (FAMEs ) by 10-fold, and in-situ derivatizations resulted in higher FAME recoverie s than derivatization after SFE. Liquid trapping enhanced recoveries of low er FAMEs when compared with tandem (solid/liquid) trapping. In-situ acetyla tions sometimes yielded acetylated glucoses during SFE. Large differences i n FAME concentrations were seen for hardwood samples, but lesser difference s were seen for the softwood pulp samples. (C) 2001 Elsevier Science B.V. A ll rights reserved.