A novel application of CO2 corrosion inhibitory potentials of banana peel extract on mild steel: Experimental studies

Abstract

The corrosion inhibitory effect of banana peel extract on mild steel in a CO2 corrosion environment is studied using weight loss method. The corrosion mechanism is studied with respect to process parameters such as the concentration of the extract, pH, temperature, and immersion time. The extract production is done using maceration method, while FTIR analysis is used to confirm the constituents of the chemical functional groups. The morphology of the corroded coupons’ surface examines SEM microscopy. The results show that the respective corrosion rate increase of 0.184–0.347 mgcm−2h−1 and 0.128–0.354 mgcm−2h−1 are obtained when temperature and immersion time increased from 35 to 75 °C and 48 to 240 h, respectively. Also, a decrease in corrosion rate of 1.01–0.128 mgcm−2h−1 and 0.035–0.0 is noted when the concentration and pH increased from 0.0001 to 1.0 g/l and 3–12, respectively. Changes in these respective experimental parameters yielding corrosion inhibitory efficiencies of (98.0–95.1), (99.1–96.0), (96.1–98.0) and (99.1–100) %. FTIR analysis confirmed the presence of electron copious functional groups such as alkane, amine, alcohol, carboxylic acid, ester and nitro compound that contain O2 and N2 atoms that can donate lone pair electrons and bind metal ions. The SEM micrographs indicated that more severity of the corrosion effects is associated with low pH and high temperature conditions. That is in good agreement with corrosion test results. Hence, a strong correlation is established between the process conditions and the corrosion mechanism. It therefore concludes that banana peel has potential for CO2 corrosion mitigation.