INVESTIGATION OF ADSORPTION AND INHIBITIVE EFFECT OF CALIXARENE DERIVATIVE NEWLY SYNTHESIZED TOWARDS C38 STEEL IN MOLAR HCl

摘要

The focus of this study is to synthesize a new calixarene derivative namely calix[6] arene (C21) and to test its performance as corrosion inhibitor of C38 steel in molar HCl at 308K. Polarization and weight loss measurements were used. Weight loss tests show that C21 retards until to stop corrosion phenomenon at 5 x 10(-5) M. C21 is an excellent inhibitor and its inhibition efficiency increases with its concentration to reach 100% since 5 x 10(-5) M. Polarization curves revealed that C21 affects both cathodic and anodic domains by decreasing current densities and then it may be classified as a mixed type inhibitor. The calixarene tested is adsorbed on the surface according to the Langmuir adsorption isotherm. Free enthalpy of adsorption reveals that C21 acts from chemisorption onto the steel surface.