以聚氨酯泡沫和2-(2-苯并噻唑基偶氮)-2-对甲酚作为分光光度试剂对钴进行选择性测定。

Selective determination of cobalt using polyurethane foam and 2-(2-benzothiazolylazo)-2-p-cresol as a spectrophotometric reagent.

作者信息

Carvalho M S, Fraga I C, Neto K C, Silva Filho E Q

机构信息

Instituto de Engenharia Nuclear CNEN, Rio de Janeiro, Brazil.

出版信息

Talanta. 1996 Oct;43(10):1675-80. doi: 10.1016/0039-9140(96)01931-5.

DOI:10.1016/0039-9140(96)01931-5

PMID:18966651

Abstract

The present work describes a selective, rapid and economical method for the determination of cobalt using the 2-(2-benzothiazolylazo)-p-cresol (BTAC) as a spectrophotometric reagent associated with a solid extraction on polyurethane foam. The BTAC reacts with Co(II) in the presence of Triton-X100 surfactant forming a green complex with maximum absorption at 615 nm. The reaction is used for cobalt determination within a pH range of 6.50-7.50, with an apparent molar absorptivity of 1.62 x 10(4) L mol(-1) cm(-1). Beer's Law is obeyed for a concentration of at least 1.60 microg ml(-1). A selective procedure is proposed for cobalt determination in the presence of Fe(II), Hg(II), Zn(II) and Cu(II) up to milligram levels using masking agents. Polyurethane foam is used for the preconcentration and separation of cobalt from thiocyanate media and this procedure is applied to its determination in nickel salts and steel alloys.

摘要

本工作描述了一种选择性、快速且经济的钴测定方法，该方法使用2-(2-苯并噻唑基偶氮)-对甲酚（BTAC）作为分光光度试剂，并结合在聚氨酯泡沫上的固相萃取。在Triton-X100表面活性剂存在下，BTAC与Co(II)反应形成一种绿色络合物，在615 nm处有最大吸收。该反应用于在pH值为6.50 - 7.50范围内测定钴，其表观摩尔吸光率为1.62×10⁴ L mol⁻¹ cm⁻¹。对于至少1.60 μg ml⁻¹的浓度，符合比尔定律。提出了一种选择性方法，使用掩蔽剂在存在高达毫克水平的Fe(II)、Hg(II)、Zn(II)和Cu(II)时测定钴。聚氨酯泡沫用于从硫氰酸盐介质中预富集和分离钴，该方法应用于镍盐和钢合金中钴的测定。