Kinetika dan Termodinamika Korosi Logam Cu dan Inhibisinya oleh Zink (Disikloheksilditiofosfat) dengan Teknik Polarisasi Potensiodinamik

Abstract

Zinc dialkyldithiophosphates (ZDTP) is a lubricant additives which has many functions such as anti-friction, anti-wear, antioxidants, and anti-corrosion. In this research, ZDTP type which was made is ZDTP with alkyl cyclohexyl group (ZDTPS). The yield of ZDTPS were 83.50% and 82.10%. Inhibition effectivity of zinc dicyclohexyldithiophosphate were 94.30% in concentration 3% and increase significantly in concentration 1%. The parameters of thermodynamics was measured to show the easiness of corrosion reaction occur. Themodynamics parameters of blank revealed ΔH∗ was 26.8583 kJ/mol, ΔS∗ was -150.4102 J/molK, and ΔG∗ was 72.4295 kJ/mol. Thermodynamics parameters of ZDTPS revealed ΔH∗ was 50.0563 kJ/mol, ΔS∗ was -79.9807 J/molK, and ΔG∗ was 74.2963 kJ/mol. Activation energy from the corrosion process with ZDTPS presence was 52.6509 kJ/mol. This value is bigger than energy activation of blank with the value was 29.4548 kJ/mol.