Spectrophotometric determination of uranium using 2-(2- Thiazolylazo)-p-Cresol (TAC) in the presence of surfactants

• Autor(a) principal: Teixeira,Leonardo Sena Gomes
• Data de Publicação: 1999
• Outros Autores: Costa,Antonio Celso Spínola, Ferreira,Sérgio Luís Costa, Freitas,Maria de Lourdes, Carvalho,Marcelo Souza de
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50531999000600016
• topic: 2-(2-Thiazolylazo)-p-Cresol; spectrophotometry; uranium determination; surfactants

A sensitive and selective spectrophotometric method is proposed for the rapid determination of uranium using 2-(2- Thiazolylazo)-p-Cresol (TAC). The reaction between TAC and uranium (VI) is instantaneous at pH 6.5 and the absorbance remains stable for over 3 h. N-cetyl-N,N,N-trimethylamonium bromide (CTAB) and triton X-100 are used for increasing the sensitivity and solubility of the system respectively. The method allows the determination of uranium in the range from 0.30 to 12.0 mug mL-1 with a molar absorptivity of 1.31 x 10(4) L mol-1 cm-1 and features a detection limit of 26 ng mL-1 at 588 nm. The selectivity of the reagent was improved by the use of (1,2-cyclohexylenedinitrilo) tetraacetic acid (CyDTA) as masking agent. The proposed method has been successfully applied to the determination of uranium in mine drainage waters. The precision (R.S.D. < 2%) and the accuracy obtained were satisfactory.