罗丹明染料光度法分别测定痕量ClO_2和Cl_2  

Spectrophotometric Determination of Trace ClO_2 and Cl_2 with Formation of Rhodamine Dye Association Particles

作　　者：周苏梅[1] 蒋治良[1] 梁爱惠[2] 温桂清[1] 康彩艳[1] 

机构地区：[1]广西师范大学环境与资源学院,广西桂林541004 [2]桂林工学院材料与化学工程系,广西桂林541004

出　　处：《广西师范大学学报（自然科学版）》2006年第3期54-57,共4页Journal of Guangxi Normal University:Natural Science Edition

基　　金：广西自然科学基金资助项目(0575042);广西新世纪十百千人才工程人选资助项目;广西师范大学博士科研启动基金资助项目

摘　　要：在pH1．42或3．09的HCl-NaAc介质中，ClO2和Cl2均能氧化I^-形成I3^-，I3^-能与罗丹明染料（Rh）形成缔合物（Rh—I3）n，导致罗丹明B（RhB）、丁基罗丹明（b—RhB）、罗丹明S（RhS）和罗丹明6G（Rh6G）缔合物微粒体系分别在558、558、526、526nm处的吸收峰降低，该体系分别在605、605、575、575nm处各产生一个新的吸收峰。c102的浓度在0．012～0．43、0．0057～0．241、0．0085～0．195、0．0060～0．49mg／L时分别与体系605、605、575、575nm处的吸光度成线性关系，其检出限分别为0．003、0．0031、0．005、0．0027mg／L。在各体系相同条件下，Cl2的浓度分别为0．0261～0．784、0．0244～0．734、0．0420．833和0．0278～0．695mg／L，遵守朗伯比尔定律，检出限分别为0．0059、0．011、0．022和0．0041mg／L。在pH为1．42条件下，可测量ClO2和Cl2共同的吸光度；用二甲亚砜掩蔽Cl2，可测量ClO2的吸光度和ClO2含量；用差减法可求出Cl2的含量。据此建立一个分别测定水中痕量ClO2和Cl2的光度法，用于水样分析，结果满意。In HC1-NaAc buffer solutions pill. 42,C102 and C12 oxidize I^- into I^-, which combines with rhodamine dye（Rh） to form （Rh-I^3）nassociation particles, resulting in decrease of absorption peak at 558 nm and a new absorption peak at 605 nm for the two particle systems of rhodamine B（RhB） and butyle rhodamine B （b-RhB）. The absorption peak at 526 nm decreases and a new absorption peak at 575 nm emerges from the two particle systems of rhodamine S（RhS） and rhodamine 6G （Rh6G）. For the four particle systems of RhB, b-RhB, RhS and Rh6G, the C102 concentrations at 0. 012-0.43, 0. 005 7-0. 241, 0. 008 5-0. 195 and 0. 006 0--0.49 mg/L are linear to the absorbance value at 605, 605, 575 and 575 nm, respectively. Their detection limits are 0. 003, 0. 003 1, 0. 005 and 0. 002 7 mg/L. In the same condition of above systems, Cl2 concentrations in 0. 026 1-0. 784, 0. 024 4-0. 734, 0. 042-0. 833 and 0. 027 8-0. 695 mg/L obey beer＇s law. Their detection limits are 0. 005 9, 0. 011, 0. 022 and 0. 041 mg/ L, respectively. In the pH 1.42 conditions, the total absorbance of ClO2 and Cl2 can be recorded. The content of ClO2 can be measured by adding DMSO to counteract the interference of Cl2, thus the concentration of ClO2 can be obtained. A new simple, rapid and accurate method for measurement of ClO2 and Cl2 was proposed with the association particle spectrophotometry in water samples with satisfactory results.

关 键 词：二氧化氯 氯气 罗丹明染料 缔合物微粒 分光光度法 

分 类 号：O657.3[理学—分析化学]