The inhibitory effects of Curcuma xanthorrhiza extract on the corrosion of API 5L X42 steel in 1M HCl solution was investigated by using weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy methods. In this study the concentration of C. xanthorrhiza extract used was 100, 250, 500, and 1000 ppm. The results show that C. xanthorrhiza inhibit the steel corrosion and acted as mixed type inhibitors. The corrosion rate decreased with the increasing of inhibitors concentrations. At the same time, inhibition efficiency increased with the increase of inhibitors concentrations. The adsorption of the extract on the steel surface was found to obey Langmuir's adsorption isotherm. The free energy value (ΔGads) indicated that the adsorption of the inhibitor molecules was typical of physisorption. It can be concluded that C. xanthorrhiza extract could be used as an alternative and environmental friendly inhibitor for API 5L X42 steel in acidic environment.
|Journal||IOP Conference Series: Earth and Environmental Science|
|Publication status||Published - 25 Jan 2018|
|Event||2nd International Tropical Renewable Energy Conference, i-TREC 2017 - Bali, Indonesia|
Duration: 3 Oct 2017 → 4 Oct 2017