QUANTUM CHEMICAL AND KINETIC PROPERTIES EVALUATION OF METHYLCHROMENO[2,3-C]PYRAZOL-3(2H)-ONE FOR ALUMINUM CORROSION INHIBITION INH2 S04 MEDIUM

Despite the advantages of its use, aluminum remains vulnerable inacidic environments. For this reason, this study evaluates the inhibition efficiency of 2 methylchromeno[2,3 c]pyrazol 3(2H) one (MCP) on aluminum corrosion in 1 M sulfuric acid solution. Gravimetric measurements were combined with quantum chemical calculations. These calculations were based on Density Functional Theory(DFT) in basis set 6-31G(d,p) with B3LYP functional. The results show that inhibition efficiency increases with concentration and immersion time, while increasing temperature reduces inhibition efficiency. The increase in activation energy in the presence of 2-methylchromeno[2,3-c]pyrazol-3(2H)-one confirms the predominance of physisorption, corroborated by activation enthalpy and entropy values, indicating endothermic dissolution with increased disorder. Theoretical calculations reveal that MCP strong inhibition activity is linked to its ability to give up and accept electrons, favouring its adsorption by physico-chemical interactions dominated by electrostatic forces. Experimental and theoretical approaches converge perfectly, confirming that the inhibitor used is promising for the protection of aluminum in acidic media at low temperatures.