铋（Ⅲ），－溴邻苯三酚红－乙基紫体系高灵敏显色反应的研究  

Studyon Highly Sensitive Colour Reac-tion of Bismuth(Ⅲ)-DBromopyrogallor Red-Ethyl Violet System

作　　者：侯明[1] 

机构地区：[1]桂林工学院应用化学系

出　　处：《分析试验室》1996年第4期61-64,共4页Chinese Journal of Analysis Laboratory

摘　　要：本文研究了在聚乙烯醇存在下，铋（Ⅲ）－溴邻苯三酚红－乙基紫体系产生的协同显色反应，在ｐＨ２．５的醋酸溶液中，形成［ＥＶ］·［Ｂｉ（ＢＰＲ）］型离子缔合物，最大吸收波长６００ｎｍ，摩尔吸光系数为４．７６×１０￣５Ｌ·ｍｏｌ￣－１·ｃｍ￣－１，铋含量在０～８．０μｇ／２５ｍＬ。范围内服从比尔定律。采用巯基棉分离干扰离子，可显著提高体系的选择性。用拟定的方法测定了铜合金中的微量铋，并根据缔合物的组成，探讨了显色反应的机理。n the presence of polyvinyl alcohol,ahighly sensitive colour reaction of Bi(Ⅲ)withbromopyrogallol red(BPR ) and ethyl violet(EV)has been studied.In an acetic acid(pH2.5 ) medium bismuth ions form an ion-associatecomplex with bromopyrogallol red and ethylviolet. The composition of the complex is Bi(Ⅲ):BPR :EV=1:1:1.The maximum ab-sorption of the ion-associate complex is at600nm,and its apparent molar absorptivity is4. 76 × 10￣5 L·mol￣-1·cm￣-1. Beer's law isobeyed in the range of 0～8. 0μg/25mL of bis-muth.After separation of the interferentialions by sulfhydryl cotton fiber,the method ishighly selective. The method has been appliedto the determination of trace bismuth in cop-per alloys with satisfactory results

关 键 词：溴邻苯三酚红 乙基紫 分光光度法 铋 铜合金 

分 类 号：O614.532[理学—无机化学] O657.32[理学—化学]