TENOXICAM PERFORMANCES FOR ALUMINIUM CORROSION INHIBITION IN 2M H2SO4: EXPERIMENTAL AND QUANTUM CHEMICAL APPROACHES

The inhibiting performances of Tenoxicam against aluminium corrosion in 2M H₂SO₄ have been tested. The results show thatinhibition efficiency increases withincrease in tenoxicam concentration,but decreases with increasing temperature. The experimental data show that the adsorption process follows the Villamil isotherm. The thermodynamic adsorption and activationfunctions were determined and analysed. The adsorption of the molecule onto the aluminium surface is an exothermic and spontaneous process. The Adejo-Ekwenchi isotherm indicatesa mixed adsorption type, but essentially physisorption at low temperature and chemisorption at high temperature. The global and local molecular descriptors confirmedthe existence of a mixed adsorption type.The QSPR studies based on two sets of energetic molecular parameters ( , ) and (  show a good reliability between inhibition efficiency and the mentioned descriptors.