一、引言随着我国稀土矿藏的大量开发和它在工业上的广泛应用,稀土合金中钍含量的简便、快速、准确测定已成为工业卫生和环境保护的一个重要课题。在现有资料中,对于用碱熔法分析矿石中的钍含量虽然有所介绍,但是,用于稀土合金样品中钍的测定报道则尚较少。本文试用碱熔法对稀土合金中钍的测定进行了研究。稀土合金粉样经过氧化钠分解后,熔块以6 N盐酸溶解。用三氯化铁共沉淀的方法,使之净化,再用0.5%PMBP-二 I. INTRODUCTION With the extensive exploitation of rare earth deposits in our country and its extensive industrial application, the simple, rapid and accurate determination of thorium content in rare earth alloys has become an important topic in industrial hygiene and environmental protection. In the existing data, although the analysis of the content of thorium in the ore by alkali melting method is described, there are few reports on the determination of thorium in rare earth alloy samples. In this paper, alkali melting method for the determination of thorium in rare earth alloys were studied. Rare earth alloy powder after sodium oxide decomposition, the clinker dissolved in 6 N hydrochloric acid. With ferric chloride coprecipitation method, make it clean, reuse 0.5% PMBP-two