阴离子树脂萃取富集-埃铬青R光度法测定赤泥中痕量钪

在pH 6.0的HAc-NaAc缓冲溶液中和溴化十六烷基吡啶（CPB）和乳化剂OP存在下，埃铬青R（ECR）与钪（Ⅲ）反应生成摩尔比为2∶1的稳定络合物。该络合物被717型阴离子树脂交换柱萃取富集后，用分光光度法测定树脂相中的钪，建立了测定钪的光度分析新方法。吸附络合物树脂相的最大吸收波长为600 nm，表观摩尔吸光系数为2.03×105 L·mol-1·cm-1，钪的质量浓度在0~200 μg/L范围内符合比尔定律。经阴离子树脂交换柱萃取富集后，钪的测定灵敏度可提高数倍，大多数常见离子不干扰测定。方法应用于铝厂赤泥中痕量钪的测定，相对标准偏差小于2%，加标回收率在98%~102%之间，测定结果同ICP-AES法的结果相一致。

Spectrophotometric determination of trace scandium in red mud using eriochrome cyanine R after extraction enrichment with anion resin

In HAc-NaAc buffer solution at pH 6.0, eriochromocyanine R （ECR） could react with scandium （Ⅲ） to form a stable complex （molar ratio of 2∶1） in the presence of cetylpyridine bromide （CPB） and emulsifier OP. This complex was extracted and enriched with 717 anion resin exchange column. The scandium in resin phase was determined by spectrophotometry. Consequently, a new spectrophotometric determination method of scandium was established. The maximum absorption wavelength of this adsorptive complex resin was 600 nm, and the apparent molar absorptivity was 2.03×105 L·mol-1·cm-1. Beer's law was obeyed for scandium in the range of 0-200 μg/L. After extraction enrichment with anion resin exchange column, the determination sensitivity of scandium could be enhanced by several times. Most common ions did not interfere in the determination. The proposed method was applied to the determination of trace scandium in red mud of aluminium plant. The relative standard deviation （RSD） was less than 2 %, and the recoveries of standard addition were 98 %-102 %. The determination results were consistent with those obtained by ICP-AES.