STUDIES ON THE DEVELOPMENT OF SENSITIVE, PRECISE, AND RAPID ANALYTICAL METHODS FOR NONFERROUS ELEMENTS USING SPECTROMETRIC DETECTIONS

The sensitive and precise determination of impurities in nonferrous me tals is important for controlling the properties of these materials. F urthermore, in order to regulate the impurities, rapid and accurate an alytical methods must be applied to the determination of various compo nents at hydrometallurgical nonferrous metal process controls. Trace a nalyses of nonferrous metals are also essential for geochemical and en vironmental studies, This thesis discusses the development and applica tion of sensitive, precise and rapid analytical methods for nonferrous elements in various samples. Anion-exchange - spectrophotometric dete rmination methods for tin and uranium and cation-exchange - atomic abs orption spectrometric determination methods of beryllium were investig ated and applied to the analyses of various environmental samples. Rap id determination methods for gallium and indium in black ore by utiliz ing graphite-furnace atomic absorption spectrometry with matrix modifi cation were also developed. Derivative spectrophotometry was applied t o the simultaneous determinations of gold-platinum-palladium, uranium- thorium, and 7 rare earth elements. Furthermore, flow-injection (FI) a nalysis systems were developed for the spectrophotometric determinatio n of impurities (cobalt, copper, and cadmium) in hydrometallurgical zi nc refining. The following new techniques were devised: a correction m ethod for the system variation, a computer-controlled variable volume sample introduction to expand the dynamic ranges of the proposed FI sy stem, and an anion-exchange mini-column system for separating cadmium in a high-salt concentration zinc sulfate solution. These systems were successfully used at the production sites for on-line monitoring, con tributing to a precise control of the quality of zinc metal.