A Blend of Pineapple Crown Extract and Red Onion Skin Extract as Green Corrosion Inhibitors

Abstract The use of red onion skin extract (ROSE), pineapple crown extracts (PCE) and a blend of the two (PR) as natural corrosion inhibitors for offshore oil and gas infrastructures and subsea pipelines is investigated in this study. The objective is to find a sustainable alternative to toxic synthetic inhibitors. The study investigates how well these extracts work to lower corrosion rates and advance environmental preservation. Carbon steel and mild steel are used as sample coupons in this research. The twenty metal coupons—ten samples for mild and carbon steel, respectively, are prepared as part of the methodology. To prevent contamination with impurities, the coupons were polished and degreased using sandpaper and acetone. Ethanol was used as a solvent to extract the inhibitors, which were then put in a magnetic stirrer and agitated for four hours. Gravimetric analysis was conducted to analyse the inhibitor effectiveness and the metal corrosion rate. The coupons were immersed in acidic saltwater solutions containing different concentrations of PCE, ROSE and PR (3ml, 6ml and 9ml). The experiment was conducted for 96 hours but the coupons were retrieved and weighed every 24 hours. The corrosion rate of the metals in the presence of PCE and ROSE was computed. PCE has the highest inhibitory efficiency for mild steel (97.67%) and carbon steel (94.81%), followed by PR (89.04% and 94.15%) and ROSE (77.66% and 94.62%). Thus providing eco-friendly corrosion inhibitors that can be employed to prevent corrosion in offshore facilities and pipelines. It gives qualitative analysis on the impact of the blend of PCE and ROSE as potential environmentally friendly inhibitors even in comparison to the industry based inhibitors.