【摘要】 <正> 测定海水中的超痕量钨时,由于含量低于微量分析方法的灵敏度极限,所以均需预先浓缩.目前文献上报道的方法有共沉淀法,离子交换法和活性炭吸附法.这些方法费时甚多,同时在浓缩与分离过程中钨有损失,影响分析的准确度,如改用有机溶剂萃取法,则可望克服这些缺点.关于钨的萃取浓缩分离,在痕量范围内,研究得较多,并且曾成功地应用在实际样品的分析中,但是在超痕量(～0.1γ/L)的萃取浓缩方面,尚未见更多还原

【Abstract】 Extractive reaction of tungsten complex with 6, 7-dihydroxy-2, 4-diphenyl-enzpyranol R) have been studied. Determination of optimum extraction conditions and composition of xtracted complex were carried out at low concentrations of tungsten. Experimental results howed that the complete extraction of tungsten was achieved with a single extraction in the ange of pH1～4. Composition of extracted complex was established to be R:W = 1:1. In 0.1 M ydrochloric acid solution, the distribution ratio of tungsten （～1γ） is given by the expression =[WO（OH）R]_o)/([W]_aq)=5.52×10⁴[HR]_oProcedures for the extractive concentration of ltramicroquantity of tungsten in sea water was proposed. Put 1 liter of water sample into a 2 liter eparatory funnel and the pH value is adjusted to ca. 1 by the addition of a calculated amonut of ydrochloric acid. Adding 15ml of 0.05% ethanolic HR solution and 20ml of chloroform, the mixture is haken vigorously for more than 5 min. and allowed to stand for the saparation of phases. The organic hase is collected and combined with washings. The proposed method is sensitive, simple and convenient. t as applied to the determination of the tungsten in river water, lake water, hot spring water and tap water ith good results.更多还原