Wuluh Starfruit (Averrhoa Bilimbi Linn.) Leaves Extract As Green Corrosion Inhibitor In Reinforced Steel

A utilization of organic inhibitors to reduce corrosion rate in metals has been widely studied compared to inorganic inhibitors because of its environmentally friendly property. In this study, the extract of Wuluh starfruit leaves (Averrhoa Bilimbi Linn.), which is contains tannins and flavonoid compounds, was used as an inhibitor to inhibit the corrosion rate in reinforced steel. The objective of this study was to analyse the effect and the efficiency of volume inhibitor variation in 3% of NaCl corrosive medium to the corrosion rate of reinforced steel. The method used is based on the losing weight, where the sample was immersed in corrosive medium mixed with an inhibitor. The study results shown that the extract of Wuluh starfruit leaves was able to inhibit the corrosion rate as 0.0004 cm/yr at the optimum inhibitor volume of 16 mL with the efficiency of 99.7%