8-氨基喹啉-5-磺酸-示波计时电位法快速测定天然水体中锌形态  

Fast Determination of Five Zinc Fractions in Water Samples by ac Adsorptive Oscillopolarography with 8-Aminoquinoline-5-Sulphonic Acid

作　　者：干宁[1,2] 

机构地区：[1]宁波大学理学院 [2]南京大学化学系,江苏南京210008

出　　处：《广东微量元素科学》2005年第3期37-44,共8页Trace Elements Science

基　　金：中国博士后基金 (No.2 10 75 0 2 3);配位化学国家重点实验室开放基金资助项目

摘　　要：报道了8 氨基喹啉5 磺酸(简称8-AQS) -示波计时电位法分别在酸性和碱性条件下测定了天然水样中的锌浓度,发现在酸性下测定的是无机不安定态锌c(Zni) ,而在碱性下测定的是总溶解态锌c(Zna)。并用该法测定了酸消化水样中的总锌c(ZnT) ,由c(Zna) -c(Zni)间接得到有机安定态c(Zn0 ) ,c(ZnT) -c(Zna)得到颗粒态酸溶态锌c(Znr) ,据此可以实现对五种锌形态的区分。测定了1 0多个实际水样,与经典的离子交换-AES方法进行了对照,结果基本一致。A simple and reliable electroanalytical method for the fast deternination of different species of znic(total Zn T,particulate acid soluble Zn r,dissolved Zn a,labile inorganic Zn i,unlabile organic Zn 0)in natural waters by ac oscillopolarography using 8-aminoquinoline-5-sulphonic acid(8-AQS)is described respectively under acidified and alkalized conditions.The method is based on the different competitve complexation capacities of 8-AQS with natural organic matter(NOM)at two pH 5.2 and 8.0.Inorganic monomeric Zn is determined at pH 5.2(0.5 mol/L NH 4Ac-HAc-5×10 -4 mol/L 8-AQS),while total monomeric Zn is determined at pH 8.0(0.5 mol/L NH 4Ac-NH 3·H 2O-5×10 -4 mol/L 8-AQS).The method is successfully employed to determine five Zn fractions in more than ten real water samples.The results are satisfactory in agreement with those of ion exchange-AES speciation method.

关 键 词：8-氨基喹啉-5-磺酸 示波计时电位法 锌形态 天然水 

分 类 号：O657.1[理学—分析化学]