Simultaneous determination of textile dyes by Adsorptive Cathodic Stripping Voltammetry

Abstract

ABSTRACT. The Adsorptive Cathodic Stripping Voltammetry (ACSV -differential pulse) proved to be an efficient method in the separation and quantification of two reactive textile dyes, Procion Yellow (PY) and Procion Red (PR), each containing two azo groups as chromophores and two monochlorotriazine reactive groups, at nanomolar level. for PR in B-R buffer pH 8.0, using preconcentration at -0.1 V during 60 s.Keywords: stripping voltammetry, reactive dyes, textile dyes. Determinação simultânea de corantes têxteis por Voltametria Adsortiva de Redissolução CatódicaRESUMO. A técnica de voltametria adsortiva de redissolução catódica (VARC -pulso diferencial) mostrou-se eficiente na separação e quantificação de dois corantes têxteis reativos, Amarelo Procion (PY) e Vermelho Procion (PR), cada um contendo dois grupos azo como cromóforos e dois grupos reativos monocloro-triazina, a nível nanomolar. A linearidade do método obtida para cada corante reativo foi 30,15 -633,15 nmol L -1 para AP em tampão B-R pH 8,0 e 62,56 -982,291 nmol L -1 para VP em tampão B-R pH 8,0, usando pré-concentração em -0,100 V por 60 s.

Derivative cathodic stripping voltammetry in the simultaneous determination of three textile dyes in aqueous solutions

“…This result is in accordance with the electrochemical reduction mechanisms for PY, PB, and PR described elsewhere . Thus, PY (peak a) and PR (peak b) can individually be determined in an aqueous binary mixture by cathodic adsorptive stripping voltammetry, as their peaks are observed separately . However, derivative voltammetry must be used for determining PY, PR, and PB (peaks c) in an aqueous ternary mixture owing to peak overlapping.…”

“…As the peak signals for the three dyes may overlap during the analysis of ternary mixtures, it is necessary to apply a derivatisation technique to identify and quantify each peak separately, as shown in Figure b. The derivatisation procedure was not necessary for the binary mixtures, as described elsewhere . Reactive dye concentrations in aqueous solutions, dyebath, and industrial effluent were efficiently determined by derivative cathodic stripping voltammetry with no interference.…”

“…Although the individual determination of dyes and pigments has extensively been described for aqueous solutions , there is insufficient information on the simultaneous determination of dyes employing derivative voltammetry techniques . The greatest problem when determining the concentration of textile dyes in either water or wastewater by voltammetry is related to the chemical similarity of the compounds, which may lead to voltammetric peak overlapping.…”

“…Procion Yellow HE4R (PY), Procion Red HE7B (PR), and Procion Blue HER (PB) are classified as reactive azo dyes and are widely employed in fabric dyeing processes in the textile industry . As mixtures of these dyes are difficult to separate, which hinders the individual detection of each dye, the aim of the present study was to develop a novel procedure for determining concentrations of PY, PR, and PB in aqueous ternary mixtures generated after an industrial fabric dyeing process.…”