ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Determination of formaldehyde by flow injection analysis with spectrophotometric detection exploiting brilliant green–sulphite reaction

Lúcio Bolognesi, Eder J. dos Santos, and Gilberto Abate

Instituto de Tecnologia do Paraná (TECPAR), 81350-010 Curitiba, PR, Brazil

E-mail: gilberto@quimica.ufpr.br

Abstract: A method for the determination of formaldehyde by flow injection analysis with spectrophotometric detection is proposed, based on retarding the reaction between brilliant green and sulphite by the addition of formaldehyde; this was investigated for formaldehyde quantification in extracts from wood-based panels. For the first time, a heating step was explored, providing a sample throughput of 50 analyses per hour, with a limit of detection of 0.02 mg L⁻¹ and linearity of 0.20-3.0 mg L⁻¹, which was adequate for the expected range of formaldehyde concentration in the extracts. The mean recovery observed for actual samples was in the range of 92-106 %, with a maximum relative standard deviation of 6.0 %. The paired t-test revealed no significant difference between this method and the official Nash method, demonstrating an appropriate accuracy and precision; the method is proposed as a simple, fast and inexpensive alternative for the routine determination of formaldehyde in an aqueous medium.

Keywords: formaldehyde determination – brilliant green-sulphite – spectrophotometry – flow injection analysis – wood-based panels

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2015-0084

Chemical Papers 69 (6) 791–798 (2015)