Adsorptive and DFT Studies of Some Imidazolium Based Ionic Liquids as Corrosion Inhibitors for Zinc in Acidic Medium

摘要

The corrosion inhibition ability of 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4 ] and- 1-decyl-3-methylimidazolium tetrafluoroborate [DMIM][BF4 ] ionic liquids (ILs) on zinc surface in1.0 M HCl at 30 - 50C was investigated using gravimetric analysis and theoretical Density FunctionalTheory (DFT) approach, using the B3LYP functional. Thermodynamic and kinetic parameters such aso G ads, Ea, S*, H* were calculated. The adsorption of ILs on zinc surface adopted the Langmuiradsorption isotherm model. The values of Ea and H* suggested a physisorption process. Bothexperimental and theoretical results show that the two ionic liquids are good corrosion inhibitors for- zinc corrosion in 1.0 M HCl solutions and their inhibition efficiency follows the order: [DMIM][BF4 ]- > [BMIM][BF4 ].