摘要
研究了浊点萃取(CPE)-紫外可见光谱法(UV/Vis)测定微量钴的新方法,利用表面活性剂聚乙二醇辛基苯基醚(TritonX-100)和配合剂2[(5-溴-2-吡啶)-偶氮]-5-(二乙氨基)苯酚(5Br-PADAP)对试样中的钴(Ⅱ)进行浊点萃取。探讨了影响浊点萃取及测定灵敏度的因素。在最佳条件下,钴的富集倍率为5,检出限为1.18ng/mL(n=11),RSD为2.8%(n=5,c(Co2+)=0.20μg/mL),钴含量在(0.01～0.5)μg/mL范围内服从比尔定律。本法对实际样品中的钴进行富集和测定,结果令人满意。
A new method based on cloud point extraction（CPE） coupled with UV-Vis for separation/ preconcentration of trace cobalt in soybean samples was proposed. Cobalt was complexed with 5Br-PADAP in an acidic medium using Triton X-100 as surfactant and quantitatively extracted into a small volume of the surfactant-rich phase after centrifugation. The chemical variables affecting CPE were investigated and optimized. Under the optimum conditions, the limit of detection for cobalt was 1.18 ng/mL（n= 11） with an enhancement factor of 25 and the relative standard deviation was 2.8% （n= 5, c（co^2＋ =0.20 ug/mL）. The experimental result showed that the high-pressure microwave-assisted acid digestion was more accurate for soybean samples. The method was applied to the determination of cobalt in reference material and soybean samples with satisfactory results.
出处
《化学世界》
CAS
CSCD
北大核心
2009年第4期209-212,共4页
Chemical World
