Inhibition Study of Low Carbon Steel Corrosion in Hydrochloric Acid Media Using Pluchea indica Less Extract

Abstract

This research aims to determine the ability of Pluchea indica Less methanol extract as an inhibitor in the low carbon steel corrosion in 1 M hydrochloric acid media. HCl solution was reacted with P. indica Less leaves extract to decelerate the process of oxidation of iron (Fe) with concentration variations of 0 ppm, 500 ppm, 1000 ppm, 1500 ppm, and 2000 ppm immersion time of 2, 4, and 6 days. The corrosion level was determined by the loss of weight and the method of potentiodynamic polarization. Low carbon steel delineation was analyzed using the instrument of Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS). The loss of weight and the method of potentiodynamic polarization indicated the lowest level of corrosion at six days of immersion with the concentration of extract of 2000 ppm, each of 2.5195109 mmpy with 97 % efficiency 2.18225455 mmpy with the efficiency of 98 %. The superficies of carbon steel immersed in HCl 1 M solution without inhibitor contained more holes and cracks than the superficies of carbon steel immersed in HCl 1 M solution in the presence of P. indica Less leaves extract. The results showed that P. indica Less leaves extract can inhibit corrosion of low carbon steel in acid media HCl 1 M. Greater extract concentration and longer immersion time result in a lower level of corrosion and greater efficiency of inhibition.