title: A single FIA system coupled with reduction and distillation processes for the determination of sulfate ion by spectrophotometry.
abstract: In the present work, all steps of the sulfate reduction procedures, such as reduction, distillation and sulfate determination were joined in only one FIA system. The formed sulfide was on-line determined by employ the Fisher reaction. The proposed method presented a LOD of 1.00 μg L(-1) and a LOQ of 3.33 μg L(-1), well lower than the most commonly used turbidimetric determination, with no significant interferences. Additionally, we reached an analytical frequency of 6 measurements per hour, including all steps, beginning with the introduction of the sample up to the signal reading. Therefore, it revealed very fast, low reagent/sample consumption, agreeing with green-chemistry statements. This method has also a wide linear range (3.33 up to 1000 μg L(-1)), being useful for both low and high sulfate concentrations.
authors.affiliation: Universidade Federal de Alfenas, Instituto de Química, R. Gabriel Monteiro da Silva, 714, 37130-000 Alfenas-MG, Brasil.
authors.forename: Ariadne M
authors.initials: AM
authors.lastname: Brondi
authors.forename: Giovana F
authors.initials: GF
authors.lastname: Lima
authors.forename: Célio
authors.initials: C
authors.lastname: Wisniewski
authors.forename: Maria J S
authors.initials: MJ
authors.lastname: Wisniewski
authors.forename: Pedro O
authors.initials: PO
authors.lastname: Luccas