Solid-liquid Separation after Liquid-liquid Extraction. -Spectrophotometric Determination of Copper， Nickel and Bismuth after Extraction of Their Diethyldithiocarbamates with Molten Naphthalene.一

摘要

A procedure for the spectrophotometric determination of copper， nickel andbismuth by mo1ten naphthalene extraction is described. Sodium diethyldithio-carbamate reacts with copper，nickel and bismuth ions to form insoluble chelateswhich are easily extracted with mo1ten naphthalene. The mixture of theirchelates and naphthalene is dissolved in dimethylformamide. The absorbanceof the solution are measured against the reagent blank at the given wavelengthand the trace amounts of copper， nickel and bismuth are determined spectrophotometricallyunder the optimum conditions. The other factors such as pH，amounts of reagent and naphthalene， stability were studied， and the molarabsorptivity，sensitivity and coefficient of variation evaluated.