微乳液介质-二溴对甲偶氮羧分光光度法测定微量锡  

Microemulsion medium-spectrophotometric determination of micro tin with dibromo-p-methyl carboxyazo

作　　者：徐国想[1] 马卫兴[1] 许兴友[1] 洪晴[1] 

机构地区：[1]淮海工学院化学工程系,江苏连云港222005

出　　处：《冶金分析》2007年第8期19-22,共4页Metallurgical Analysis

基　　金：江苏省海洋生物技术重点建设实验室基金项目(2006HS020)与江苏省应用化学重点建设学科项目(2005)

摘　　要：研究了由十六烷基三甲基溴化铵（CTMAB）、正丁醇、正庚烷和水自制微乳溶液存在下，二溴对甲偶氮羧（DBpMCA）与Sn（Ⅳ）的显色反应，建立了分光光度法测定微量锡的新方法。结果表明，在pH10．4的NH4Cl—NH3·H2O缓冲溶液中，Sn（Ⅳ）与试剂形成组成比为1：3的紫红色络合物，该络合物的最大吸收峰在542nm波长处，表观摩尔吸光系数ε为1．04×10^5L·mol^-1·cm^-1。在10mL显色液中，Sn（Ⅳ）量在0．02～12μg范围内符合比尔定律，检出限为6．0×10^-4μg／mL。方法已用于粉煤灰中微量锡的测定，回收率为99．4％～101．6％，相对标准偏差为0．59％～1．06％。The color reaction of the reagent dibromo- p -methyl carboxyzo（DBpMCA） with Sn（Ⅳ） in the presence of CTMAB microemulsiom was studied,and a new spectrophotometric method for the determination of micro tin has been established. Resuhs show that the new color reagent reacts with Sn（Ⅳ）to form a stable purple-red complex（mole ratio 1 ： 3）in the presence of NH3·H2O-NH4Cl buffer solution at pill0.4. The maximum absorption wavelength and apparent molar absorptivity are 544 nm and 1.04×10^5 L·mol^-1·cm^-1 respectively. Beerrs law is obeyed in the range of 0.02-12μg in 10 mL experimental liquor. The detection limit is 6 × 10^-4 μg/ mL. The method has been applied to the direct determination of tin in fly ash with the recovery of 99.40%-101.6 % and the relative standard deviation of O. 59%-1.06%

关 键 词：二溴对甲偶氮羧 分光光度法 锡 

分 类 号：O657.32[理学—分析化学]