M Donaldson E
Mineral Sciences Laboratories, Canada Centre for Mineral and Energy Technology, Department of Energy, Mines and Resources, Ottawa, Canada.
Talanta. 1988 Jan;35(1):47-53. doi: 10.1016/0039-9140(88)80010-9.
A method for determining approximately 0.2 mug/g or more of arsenic in ores, concentrates and related materials is described. After sample decomposition arsenic(V) is reduced to arsenic(III) with titanium(III) and separated from iron, lead, zinc, copper, uranium, tin, antimony, bismuth and other elements by cyclohexane extraction of its xanthate complex from approximately 8-10M hydrochloric acid. After washing with 10M hydrochloric acid-2% thiourea solution to remove residual iron and co-extracted copper, followed by water to remove chloride, arsenic is stripped from the extract with 16M nitric acid and ultimately determined in a 2% nitric acid medium by graphite-furnace atomic-absorption spectrometry, at 193.7 nm, in the presence of thiourea (which eliminates interference from sulphate) and palladium as matrix modifiers. Small amounts of gold, platinum and palladium, which are partly co-extracted as xanthates under the proposed conditions, do not interfere.
描述了一种测定矿石、精矿及相关物料中约0.2μg/g或更多砷的方法。样品分解后，用三价钛将五价砷还原为三价砷，并通过从约8 - 10M盐酸中用环己烷萃取其黄原酸盐络合物，使其与铁、铅、锌、铜、铀、锡、锑、铋及其他元素分离。用10M盐酸 - 2%硫脲溶液洗涤以除去残留的铁和共萃取的铜，然后用水除去氯离子，用16M硝酸从萃取物中反萃取砷，最终在2%硝酸介质中，于193.7nm处，在硫脲（消除硫酸盐干扰）和钯作为基体改进剂存在的条件下，通过石墨炉原子吸收光谱法测定。在所提出的条件下，部分以黄原酸盐形式共萃取的少量金、铂和钯不产生干扰。
