EXPLORING THE GREEN POTENTIAL OF RHIZOPUS-DERIVED BIOSURFACTANT FOR CORROSION INHIBITION IN MILD STEEL

• Published in: Journal of Engineering Science and Technology
• Main Author: Rayeg O.A.; Petrus C.; Huap A.C.; Nyuin J.; Marajan C.; Tawie R.
• Format: Article
• Language: English
• Published: Taylor's University 2024
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85197609808&partnerID=40&md5=a4d02e8cb5f5b7cc17ef8f8ab975a3af

Corrosion poses significant challenges in construction and manufacturing, impacting aesthetics and structural integrity. This study evaluates the efficacy of Glycerolipids biosurfactant, derived from the soil fungus Rhizopus, in inhibiting corrosion on mild steel bars. The biosurfactant was cultivated in Mineral Salt Medium (MSM) broth supplemented with waste frying oil as the sole carbon source via aerobic batch fermentation for 40 days, with harvesting at a concentration of 1gml-1, meeting emulsification index, drop collapse, and oil spreading test criteria. Biosurfactant's inhibition efficiency was evaluated through Scanning Electron Microscope analysis, weight loss experiments, and electrical resistivity tests. The specimens were immersed for 100 days in saline solutions with biosurfactant concentrations ranging from 5% to 20% (v/v). Comparative analyses were conducted with control specimens treated with the synthetic surfactant, Tween 80. The findings establish a direct correlation between biosurfactant concentration and corrosion inhibition efficacy, resulting in a reduced corrosion rate of mild steel bars. The results indicated that adding biosurfactant up to 17.5% of the volume of saline solution inhibited corrosion at 71.94% efficiency, with a corrosion rate of only 0.0201 mm/year. These findings highlight the potential of Glycerolipids biosurfactant as an eco-friendly corrosion inhibitor for mild steel. © School of Engineering, Taylor’s University.