GREEN GUARDIANS: BANANA PEELS AND GUAVA LEAVES AS CORROSION INHIBITOR FOR LOW CARBON STEEL

Abstract

Low carbon steel presents several challenges, one of which is its high susceptibility to corrosion compared to other types of steel. Rust is a visible indicator of this corrosive process and can potentially lead to severe structural engineering issues. The use of certain substances or chemical compounds added to corrosive environments can prevent or reduce metal corrosion; however, due to their toxicity, traditional chemical-based corrosion inhibitors are becoming less acceptable. This study aimed to investigate the use of eco-friendly or organic corrosion inhibitors derived from banana peels and guava leaves as an initiative toward adopting a more environmentally conscious approach to corrosion resistance. The study utilized a true experimental research design to determine the efficiency of organic corrosion inhibitors on low carbon steel. Ethanolic extracts of combined banana peels and guava leaves were prepared and used as the organic corrosion inhibitor. A weight loss test was conducted to measure inhibitor efficiency. The steel samples were initially weighed, then exposed to various corrosion conditions through salt spray testing, both with the organic inhibitor and with a commercially available chemical-based corrosion inhibitor. After the procedure, the steel samples were weighed again to determine weight reduction. Lower weight loss indicated greater corrosion inhibition efficiency. The results showed that the combined banana peel and guava leaf extract inhibited corrosion in low carbon steel with a 95% efficiency rate. In comparison, the commercially available corrosion inhibitor (WD-40) exhibited a 90% efficiency rate. In the weight loss test, steel samples treated with the organic extract lost only 0.1 mg of weight, while those treated with the conventional inhibitor lost 0.2 mg. The findings indicate a significant difference in the efficiency between organic corrosion inhibitors derived from banana peels and guava leaves and conventional chemical-based inhibitors. This variation is attributed to their ability to inhibit rust formation on steel. Banana peels and guava leaves provide corrosion inhibition due to the presence of compounds such as tannins and flavonoids. In contrast, commercially available corrosion inhibitors demonstrated lower efficiency. The combined extracts of banana peels and guava leaves show strong potential as effective organic corrosion inhibitors for protecting low carbon steel from corrosion.