聚烯丙基硫脲的合成及其富集分离金和钯

Selective separation and enrichment of trace Au(Ⅲ) and Pd(Ⅳ) with poly-allylthiourea sorbent

一种新型的固相萃取吸附材料聚烯丙基硫脲被合成并用于水溶液中痕量Au(Ⅲ)和Pd(Ⅳ)的富集分离.分析的过程是基于被分析物以硫脲复合物的形式保留在螯合树脂上.研究了共存离子的干扰、螯合树脂的吸附容量以及pH值、富集时间、洗脱剂体积等参数对吸附的影响.待测离子的吸附回收率大于96%.在最优条件下,新型吸附剂对Au(Ⅲ)和Pd(Ⅳ)的最大吸附容量分别为3.23,3.84mmol/g.吸附剂对目标离子的吸附行为可以通过兰格缪尔吸附等温式来描述.该方法用于实际样品中Au(Ⅲ)和Pd(Ⅳ)的富集分离获得了令人满意的效果.

A new solid-phase extractant poly-allylthiourea was prepared and characterized for selective separation and enrichment of trace Au（Ⅲ） and Pd（Ⅳ） from aqueous solution. This procedure is based on the retention of analyte in the form of thiourea complex on polymer resin. Several parameters, such as distribution coefficient and adsorption capacity of the chelating resin, pH and time of uptake and striping, volume of sample and eluent, were evaluated using model solutions. The effects of electrolytes and cations on the enrichment were also investigated. The recoveries were 〉 96%. At optimal conditions, the maximum extraction capacity of the new sorbent was 3.23 and 3.84 mmol/g for Au（Ⅲ） and Pd（Ⅳ）, respectively. The adsorption behavior of target ions on the sorbent could be described by Langmuir adsorption isotherm equation. The developed method was applied to the separation and enrichment of trace Au（Ⅲ） and Pd（Ⅳ） in synthetic samples with satisfactory results.