An automatic flow-analysis procedure for spectrophotometric determination of cationic surfactants in surface water using a solenoid micro-pump for propelling solutions of reagents and sample is described. The proposed method is based on a ternary formation complex between chromazurol S, the Fe(III) ion, and the cationic surfactant. The flow network comprised four solenoid micro-pumps controlled by a microcomputer, which performed the sampling step by loading a reaction coil with sample and reagent solutions and displacing the sample zone through the analytical path. The system is simple, easy to operate, and very flexible, with sufficient sensitivity to determine cationic surfactants in water without any pre-concentration or separation step. After determining the best operational conditions, favourable features such as a linear response between 0.34 and 10.2mgL −1 of surfactant ( R =0.999), a relative standard deviation of 0.6% ( n =11) for a sample containing 3.4mgL −1 of surfactant, a detection limit of 0.035mgL −1 of surfactant, and a sampling throughput of 72 determinations per hour were achieved. The system was used to determine cationic surfactant in river-water samples, and recovery values between 91 and 106% were achieved.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
Document Type: Research Article
Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Av. Centenário 303, Piracicaba 13400-970, CP 96, SP, Brazil
Faculty of Chemistry, Department of Analytical Chemistry, University of Valencia, Research Building, 50 Dr. Moliner St., 46100 Burjassot, Valencia, Spain
August 20, 2006
More about this publication?