Corrosion inhibition of aluminium alloy by rhamnolipid biosurfactant derived frompseudomonassp. PS-17

Abstract

Purpose The purpose of this paper is to study the influence of rhamnolipid biosurfactant complex on the corrosion and the repassivation of a freshly cut Al-Cu-Mg aluminium alloy surface. Design/methodology/approach The electrochemical methods, supported by quantum-chemical calculations and scanning electron microscopy data, were used. Findings It was established that the rhamnolipid biosurfactant effectively inhibits corrosion of the alloy in synthetic acid rainwater. The efficiency of inhibition becomes stronger with the increase of biosurfactant concentration; however, above the critical micelle concentration, the further improvement in inhibition is minor. It is believed that the mechanism of corrosion inhibition is related to the adsorption of the biosurfactant molecule on the aluminium alloy surface and the formation of a barrier film; however, the formation of a complex compound (salt film) between aluminium ions and rhamnolipid on anodic sites of the alloy is not ruled out. In case of surface mechanical activation of the alloy, the biosurfactant molecule effectively prevents corrosion. Furthermore, addition of the biosurfactant to the corrosion environment increases the repassivation kinetics of the alloy by two to four times as compared with an uninhibited environment. Practical implications The commercial impact of the study consists in the possibility of obtaining of environmentally safe corrosion inhibitors of aluminium alloys by biosynthesis from renewable agricultural raw materials. Originality/value The originality of this paper is to study the effectiveness of “green” corrosion inhibitor based on biogenic product on freshly generated surface of aluminium alloy.

Aluminium alloy corrosion inhibition by a two-stage modified nanoporous zeolite

“…The shift of the phase angle θ maximum (Figure 9, curves 4 and 5) towards higher frequencies indicates the formation of a protective phosphate layer on the surface of the aluminium alloy [28]. The appearance of a second smaller peak on the phase angle dependencies 1, 2, 3 (Figure 9) in the frequency range of 50-200 Hz in addition to the first big one near 1 Hz indicates the presence of a defective surface film on aluminium alloy with insufficient protective properties.…”

Application of Biomass Corrosion Inhibitors in Metal Corrosion Control: A Review

“…Zin [ 25 ] investigated the effect of rhamnolipid biosurfactant complexes on the corrosion and passivation of freshly cut aluminum–copper–magnesium aluminum alloy surfaces. It was demonstrated that the rhamnolipid biosurfactant effectively inhibited the corrosion of the alloy in synthetic acidic rainwater.…”

Biosurfactants: Eco-Friendly and Innovative Biocides against Biocorrosion

“…Zin et al [59] studied the influence of surface-active rhamnolipid biocomplex produced by the Pseudomonas sp. PS-17 on the corrosion and the repassivation of a freshly cut Al-Cu-Mg aluminum alloy surface.…”

“…Bacillus species Lipopeptides Antagonistic effects against a broad spectrum of microorganisms [38,43] Bacillus amyloliquefaciens, Bacillus subtilis Peptide, lipopeptides Antagonistic effects against many fungal pathogens [69,70] Bacillus subtilis Surfactin Inhibit biofilm formed by Salmonella enterica, E. coli, and Proteus mirabilis [51] Pseudomonas sp. PS-17 Rhamnolipids Inhibit corrosion of alloy [59] Pseudomonas spp. Rhamnolipids Algicidal, anti-amoebal and zoosporicidal properties [47,49] Pseudomonas fluorescens Biosurfactant Inhibit corrosion of stainless steels [58] Pseudomonas stutzeri F01 Biosurfactant Antibacterial properties to corrosive bacterial strains [61]…”