【作者】 朱圆圆；

【导师】 苏耀东；

【作者基本信息】 同济大学 ， 分析化学， 2008， 硕士

【摘要】 浊点萃取（cloud point extraction,简称CPE）法是近年来出现的一种新兴的液-液萃取技术。它以表面活性剂胶束水溶液的溶解性和浊点现象为基础,通过改变实验参数,将疏水性物质与亲水性物质分离。它具有经济、安全、高效、简便等优点,已广泛用于生命科学、环境科学等领域。近年来浊点萃取法也成功地用于金属元素的分离富集,并与分析仪器联用,用于痕量金属元素的检测。火焰原子吸收光谱法（FAAS）是痕量元素分析中常用的方法之一。由于试样的复杂和极低的含量,传统的前处理方法已经不能适用于痕量元素的分析,往往要求在测定之前用化学分离/预富集手段以分离富集待测物和除去干扰基体,以提高分析方法的灵敏度、选择性、准确性和达到更低的检出限。本论文利用螯合剂1-（2-吡啶偶氮）-2-萘酚（PAN）、吡咯烷二硫代甲酸铵（APDC）和非离子表面活性剂Triton X-100、OP-7进行浊点萃取火焰原子吸收光谱法测定痕量元素。探讨了溶液pH、试剂浓度等实验条件对以下3个体系的浊点萃取效率及测定灵敏度的影响。（1）PAN—Triton X-100体系:在最佳条件下,溶液pH为11.0时对Mn²⁺进行浊点萃取。在此条件下,Mn²⁺的检出限为7.4ng·mL^-1。（2）PAN—OP-7体系:在最佳条件下,溶液pH分别为11.0、9.0、8.0、8.0、8.0、7.0时对Mn²⁺、Cd²⁺、Ni²⁺、Pb²⁺、Cu²⁺和Co²⁺进行浊点萃取。在此条件下,各离子的检出限分别为0.011μg·mL^-1、6.6ng·mL^-1、0.027μg·mL^-1、0.066μg·mL^-1、8.5ng·mL^-1和0.026μg·mL^-1。方法用于测定环境水样中的铜,标加回收率为100.8%,相对标准偏差为3.36%（n=10）,结果令人满意。（3）APDC—OP-7体系:在最佳条件下,溶液pH为5.0时分别对Cu²⁺和Co²⁺进行浊点萃取。在此条件下,Cu²⁺和Co²⁺的检出限分别为0.013μg·mL^-1和0.052μg·mL^-1。更多还原

【Abstract】 Cloud point extraction（CPE）is a new liquid-liquid extraction which is based on the solubility and cloud point phenomenon of aqueous solutions of surfactants, upon alteration of the experimental conditions such as pH value of solution.The solution is separated into phases,which results in the separation of hydrophobe and hydrophile.CPE is an easy,safe,high efficiency and inexpensive methodology for preconcentration and separation.It has been widely used in the study of life sciences, environment sciences,and the preconcentration and separation of metal elements.Flame atomic absorption spectrometry is one of common methods in analyzing trace elements.Traditional preconcentration method is not satisfactory because of samples with small-volume and metal elements with trace content.Separation and preconcentration procedures prior to trace element determination have been explored to achieve more accurate,reliable and sensitive results and lower detection limits.The CPE method was based on employing Triton X-100 and OP-7 as nonionic surfactant,1-（2-Pyridylazo）-2-Naphthol（PAN）and Ammonium pyrrolidinedithiocar-bamate（APDC）as complexing reagent.The chemical variables affecting the detection process were optimized in the following 3 systems.（1）In PAN—Triton X-100 system,the detection limit of manganese is 7.4ng·mL^-1at pH 11.0 under the optimum conditions.（2）In PAN—OP-7 system,the detection limits of manganese,cadmium,nickel, lead,copper and cobalt is 0.011μg·mL^-1,6.6ng·mL^-1,0.027μg·mL^-1,0.066μg·mL^-1, 8.5ng·mL^-1and 0.026μg·mL^-1at pH 11.0,9.0,8.0,8.0,8.0 and 7.0 respectively.The proposed method was applied to the determination of copper in river waters.The standard addition recovery of copper is 100.8%and RSD is 3.36%（n=10）.（3）In APDC—OP-7 system,the detection limits of copper and cobalt is 0.013μg·mL^-1and 0.052μg·mL^-1at pH 5.0 under the optimum conditions.更多还原