Determinação espectrofotométrica de ácido glicólico com ácido cromotrópico assistida por forno de microondas
Nenhuma Miniatura disponível
Data
2002-12-01
Autores
Gigante, Andréa Cristina [UNESP]
Pezza, Leonardo [UNESP]
Pezza, Helena Redigolo [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
In this work, a rapid, simple and selective spectrophotometric for the determination of glycolic acid is proposed. This method is based on selective reaction between the formaldehyde splitted off by the glycolic acid, which reacts with chromotropic acid in a phosphoric acid medium, producing a violet-red compound (λmax = 570 nm). The colored compound formation was accelerated by irradiating the reacting mixture with microwave energy for 30 seconds (1.100 W). Beer's Law is obeyed in a concentration range of 0-2, 208 mg L-1. The proposed method was applied in the analysis of comercial samples of glycolic acid. Recoveries were within 97% to 101.4%, with standard deviations ranging from 0.2% to 0.4%.
Descrição
Palavras-chave
Chromotropic acid, Glycolic acid, Irradiation by microwave, Spectrophotometry
Como citar
Ecletica Quimica, v. 27, p. 223-230.