Determination of volatile corrosion inhibitors by capillary electrophoresis

In this work, a capillary electrophoresis (CE) method using indirect UV detection (214 nm) for the simultaneous determination of monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), diethylethanolamine (DEEA), monocyclohexylamine (MCHA) and dicyclohexylamine (DCHA) in water/ethanol extracts of wrapping materials containing volatile corrosion inhibitors (VCIs) was described. A running buffer consisting of 0.010 mol L−1 imidazole, 0.010 mol L−1 2-hydroxyisobutyric acid (HIBA) and 0.010 mol L−1 18-crown-6 ether enabled separation of the analytes in less than 7 min. A few method validation parameters were determined revealing good migration time repeatability (<0.7% RSD) and area repeatability (<1.8% RSD). Limits of detection were in the range of 0.52–1.54 mg L−1. Recovery values were in the range of 94.8–100.9%. The methodology was successfully applied to the analysis of three commercial products (VCI treated paper, foam and plastic). The concentration of amines in these materials varied from 0.050 to 22.3% (w/w).