微乳液介质-5-Br-PADAP分光光度法测定原油及润滑油中钴  

Microemulsion medium-spectrophotometric determination of cobaltⅡ in crude oils and lubricating oils with 2-(5-bromo-pyridylazo)-5-diethylaminophenol

作　　者：吴丽香[1] 周鸿刚 

机构地区：[1]辽宁石油化工大学石油化工学院,辽宁抚顺113001 [2]兰州石化公司炼油厂质检室,甘肃兰州730060

出　　处：《冶金分析》2006年第2期79-81,共3页Metallurgical Analysis

摘　　要：以水体积分数80％的油／水型（十二烷基硫酸钠-正丁醇-正庚烷-水）微乳液为介质，2-（5-溴-吡啶偶氮）-5-二乙氨基苯酚（5-Br-PADAP）为显色剂，分光光度法测定原油和润滑油中钴，并对测定条件进行考察。结果表明：络合物最大吸收峰位于560nm处；在25mL溶液中，钴含量在0～20μg范围内服从比尔定律，其表观摩尔吸收系数ε560=8．48×10^4L·mol^-1·cm^-1；采用柠檬酸三钠和硫脲作为联合掩蔽剂可消除其它离子的干扰。方法用于测定辽河原油和锦减四线油中钴，加标回收率分别为98．9％～104．6％和95．4％～102．6％，其相对标准偏差分别为1．5％和2．7％。With oil- 80% H2O（O/80% W） microemulsion （SDS- n-C4HgOH- n-C7H16- H2O） as medium, 2- （5-bromo-pyridylazo）-5-diethylaminophenol （5-Br-PADAP） as chromogenic reagent, the determination of cobalt（H） in crude oils and lubricating oils was achieved by spectrophotometry,and the determination conditions were studied. The results showed that the maximum absorption wavelength of the complex formed by Co（U） with 5-Br-PADAP was located at 560 nm. The apparent molar absorptivity was 8.48 × 10^4 L·mool^- 1· cm^- 1. Beer＇ s law was obeyed in the concentration range of 0 - 20μg/25 mL for cobalt. Other interference ions were eliminated by soldium citrate and sulfourea. Co^2 ＋ in Liaohe crude oil and Jiansixian （Jinzhou） were determined with relative standard deviation of 1.5 % and 2.7 %. The recovery was 98.9 % - 104.6 % and 95.4 % - 102.6 %, respectively.

关 键 词：微乳液 5-BR-PADAP 原油 润滑油 钴 分光光度法 

分 类 号：O657.3[理学—分析化学] TE622.1[理学—化学]