E. Dziwiński, G. Cote, D. Bauer
Feb 1, 1995
Abstract The composition of distilled KELEX® 100, KELEX® 100S and KELEX® 108 was nvestigated by GC/MS. Distilled KELEX® 100 and KELEX® 100S are shown to be of high and similar quality. 7-(4-Ethyl-l-methyloctyl)-8-hydroxyquinoline is the main component of these two reagents. However, the latter still contain small amounts of inert, furoquinoline-type impurities; namely 3-ethylfuro[2,3-h]quinoline and 2-(2-ethylhexyl)-3-methylfuro[2,3-h]quinoline. KELEX® 100S is probably obtained by fractionation of KELEX® 100. Except for the rate of phase separation, comparison of the composition of KELEX® 100 and KELEX® 100S does not reveal any clear reason why KELEX® 100S possesses improved properties compared to KELEX® 100, especially as far as the resistance against oxidation or the kinetics of metal extraction are concerned. KELEX® 108 is shown to contain mainly 7-(2-ethylhexyl)-8-hydroxyquinoline, but also important amounts of 8-hydroxyquinoline and its di(2-ethylhexyl) derivative.