罗丹明6G共振光散射法测定废水中铊  

Determination of thallium in wastewater by resonance light scattering method with Rhodamine 6G

作　　者：邓湘舟[1] 吴颖娟[2] 耿新华[1] 王怡[1] 张鸿郭[2] 

机构地区：[1]广州大学化学化工学院,广东广州510006 [2]广州大学化学环境科学与工程学院,广东广州510006

出　　处：《冶金分析》2014年第4期42-46,共5页Metallurgical Analysis

基　　金：国家自然科学基金资助项目(2012-4173100)

摘　　要：在硫酸介质中，痕量铊（Ⅲ）与碘化钾反应生成I3-，I3-与罗丹明6G形成1：1缔合物，可导致共振光散射明显增强，据此建立了共振光散射测定痕量铊（Ⅲ）的新方法。考察了它们的光谱特征：罗丹明6G溶液的共振荧光峰波长为540nm，（Rh6G-I3）n缔合微粒共振散射峰波长为330、420、580nm。通过条件试验确定0．4mL0．2mol／L硫酸作为反应介质、0．1mol／LKI溶液用量为0．4mL、1．0×10^-4mol／L罗丹明6G溶液用量为0．4mL、反应时间为5min。进一步考察发现，在580nm波长，共振散射光强度增加值与溶液中铊（Ⅲ）浓度呈线性关系，方法的线性范围为0．005%--0．10mg／L，检出限为0．0012mg／L。方法应用于工业废水中铊含量的测定，结果与ICP—MS法的对照结果基本一致，相对标准偏差（RSD，n=6）为1．89／6～3．29／6。In sulfur acid, trace thallium（Ⅲ） reacted with potassium iodide.and generated I3- to form com- plex （1 ： 1） with Rhodamine 6G, resulting in significant enhancement of resonance light scattering. Accordingly, a novel method for the determination of trace T1（Ⅲ） by resonance light scattering was de- veloped. The spectrum characteristics were investigated, the resonance fluorescent peak of Rhodamine 6G was at 540 nm and the resonance fluorescent peaks of （Rh6G-I3）n complex particles were at 330,420, 580 nm. Through condition test, it was determined that 0.4 mL of 0.2 mol/L sulfur acid was used as the medium, 0.4 mLof0.1 mol/L KI solution and 0.4 mL of 1.0×10 ^-4 mol/L Rhodamine 6G was used, and the reaction time was 5 min. Through further investigation, the intensity increment of resonance scattering light showed linear relationship with T1（Ⅲ） at 580 nm. The linear range was 0. 005-0.10 mg/L. The detection limit was 0. 001 2 mg/L. The proposed method was applied to the determination of T1 in industrial wastewater, whose results were basically consistent with those of ICP-MS. The relative standard deviation （RSD, n= 6） was 1.8 %-3.2 %.

关 键 词：共振散射 罗丹明6G 铊(Ⅲ) 离子对缔合物 废水 

分 类 号：O657.32[理学—分析化学]