Development of naphthenic acid fractionation with supercritical fluid extraction for use in wood decay testing

Abstract

In recent years, the performance of copper naphthenate as a wood preservative has been in question. To understand the varying results of copper naphthenate in preventing wood decay, a closer look at eight naphthenic acid (NA) supplies was undertaken. Initial studies of NA samples from individual suppliers revealed large differences in chemical composition and wood preservation ability. Samples were rated from best to worst determined by percent weight loss due to fungal activity. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that one of the intermediate quality wood preservatives from our wood decay studies contains a large portion of phenolic and aliphatic impurities in addition to the naphthenic acid components. To determine the effect of the impurities on the efficacy studies, we developed a method using supercritical fluid extraction (SFE) to remove them from the sample without changing the characteristics of the naphthenic acid composition. Comparison of NA SFE extracts continues.

Citation

Niemi, Brett; St. John, Wayne; Woodward, Bessie; DeGroot, Rodney; McGinnis, Gary. 2000. Development of naphthenic acid fractionation with supercritical fluid extraction for use in wood decay testing. Proceedings of the Ninety-Fourth Annual Meeting of the American Wood-Preservers'' Association ... Scottsdale, Arizona, May 17-19, 1998. Volume 94. Granbury, Tex. : American Wood-Preservers'' Association, 2000: Pages 165-177