Synchronous Fluorometric Determination of Trace Amounts of Anthracene in Fluoranthene Using Dibenzofuran as a Zone-melting Medium for the Separation

Abstract

Trace amounts of anthracene can be separated from fluoranthene and most of the concomitant impurities by a zone-melting technique using dibenzofuran as a zone-melting medium. Anthracene thus separated can be determined by synchronous fluorescence spectrometry without removal of dibenzofuran. The determination limit is 2 ppm. After 100 mg of a fluoranthene sample and 4 g of purified dibenzofuran had been uniformly mixed, the mixture was charged in a glass tube with an i.d. of 4 mm. The zone-pass was repeated 20 times with an upward travel at a speed of 100 mm/h under constant stirring. The lower half of the zone-molten ingot was cut out exactly and dissolved in xylene. Anthracene could be determined from the synchronous fluorescence intensity at 384 nm.