Title: Voacanga Africana As A Green Corrosion Inhibitor On Concrete Sewers
Authors: WILLIAM-PORBENI,D. OGBRERYO,S. GUMUS,R.H. TUAWER, T.J
Volume: 9
Issue: 6
Pages: 61-67
Publication Date: 2025/06/28
Abstract:
This study aims to investigate the inhibition of microbial concrete degradation mediated by acidithiobacillus thiooxidans in sewer wastewater using Voacanga Africana leaf extracts as an inhibitor. concrete samples were subjected to biogenic sulfuric acid corrosion in sewer wastewater for 26 months, the corroded concreted cubes were thereafter coated with plant extracts and subjected to sewer water for a further 5 weeks. Variations in weight loss, pH, and sulfate concentration were used to evaluate the effects of plant extracts on biogenic sulfuric acid corrosion of the coated concrete samples. The decline in SOB population, concentration, and formation of corrosion by-products were recorded. Corrosion rates of the raw concretes before coating were between 0.343364mpy - 1.323614 mpy. phytochemical analysis of the ethanolic extracts was positive for saponins, tannins, terpenoids flavonoids and alkaloids. GC-MS study of Voacanga Africana ethanolic extracts revealed the presence of 83 components. The major constituents were identified as; Thymol, Phenol, Pentanoic acid, and Eugenol. Biocorrosion control assessed the effects of plant extracts on concrete corrosion in sewer waters. A significant decline in corrosion rates with extract coating was observed for all extract coated concretes (0.001486mpy - 0.002622mpy). An increase in extract concentration was found to increase the inhibitory efficiency, which ranged from 68% to 72%. Scanning electron microscopy and X-ray diffractive analysis revealed differences in the morphology of the concrete before and after coating.