碳化钨、钨及其复合物料中痕量砷的测定

Determination of Trace Arsenic in Tungsten Carbide Sample

对碳化钨样品中的痕量砷进行了分析测定,试样以硝酸、氢氟酸低温溶解,硫—磷混酸冒烟驱除硝酸和氢氟酸,用预还原剂还原高价砷(Ⅴ)为低价砷(Ⅲ),进行氢化物原子吸收光谱测定,测得结果与摄谱法及分光光度法结果一致。

A method for the determination of trace arsenic in tungsten carbide is proposed. The method is based on the hydride generation technique on-line coupling with atomic absorption spec-trophotometry. The tungsten carbide sample is dissolved in a hydrofluoride and mitric acid mixtrue, and fumed with sulfuric and phosphoric acid mixture. And then reductants are added to transfer the pentavalent state As (Ⅴ) to the trivalent state As ( Ⅲ ), which is determined by HG-AAS with satisfactory results. The said method is simple, rapid, and sensitive, and It can be used to determine arsenic of content as low as 0. 0001 % in the kind of tungstent base samples.