碘量法测定铟锡氧化物靶材废料中锡

Determination of tin in indium tin oxide target waste by iodometry

提出了一种测定铟锡氧化物（ITO）靶材废料中锡量的分析方法，并对ITO靶材废料样品的分解方法、还原酸度的范围、基体和共存元素的干扰进行了探讨。结果表明：采用过氧化钠熔融分解样品，以铁粉还原、过滤分离部分共存元素，还原酸度（V／V）控制在359／6～50％，在保护气氛下，用铝片将锡还原为二价锡，以淀粉为指示剂，碘量法测定锡时，效果较佳。采用方法对国内外6个ITO靶材废料代表试样进行分析，结果与电感耦合等离子体原子发射光谱法（ICP—AES）吻合，10次平行测定的相对标准偏差（RSD）为0．29％～1．5％，加标回收率在99％～100％之间。

A iodometry method for determination proposed. Moreover, the decomposition method of tin in indium tin oxide （ITO） target waste was of ITO target waste sample, the range of reducing acidity, the interference of matrix and coexisting elements were discussed. The results showed that, the optimum conditions for determination of tin by iodometry with starch as indicator were as follows. the sample was decomposed by fusion with sodium peroxide; coexisting elements were separated by filtration after reduction with iron powder; the reducing acidity （V/V） was controlled in range of 35%-50%; the tin was reduced to divalent with aluminum sheet under protective atmosphere. The proposed method was applied to determination of six representative ITO target waste samples at home and abroad. The results were consistent with those obtained by inductively coupled plasma atomic emission spectrometry （ICP-AES）. The relative standard deviation （RSD, n=10） was 0.29%-1.5%, and the recoveries were between 99% and 100%.