Inhibitive action of hexadecyltrimethylammonium bromide (HDTAB) on aluminium alloy (AA3003) corrosion in hydrochloric acid medium

摘要

The inhibitive effect of hexadecyltrimethylammonium bromide (HDTAB) on the corrosion of aluminium alloy (AA3003) in 1 M hydrochloric acid medium was studied by weight loss method in relation to the temperature (25 to 55°C) and inhibitor concentration range 5.10-4to 10-2M. This study showed that the inhibitor adsorbs on aluminium alloy (AA 3003) according to the modified Langmuir adsorption isotherm; the inhibitor efficiency decreases with increasing temperature. Adsorption free energies (ΔG°ads) and apparent activation energies (Ea) were determined. The Adsorption free energies reveal that the adsorption process is spontaneous. Furthermore, some adsorption thermodynamic parameters (ΔH°ads, ΔS°ads, Qads) were estimated. Phenomenon of physical adsorption was proposed from the thermodynamic functions of adsorption and activation parameters obtained.