Investigation of the bactericidal-inhibitory effect of sulfonateand benzalkonium chloride-based substance against corrosion caused by hydrogen sulfide (H2S), carbon dioxide (CO2), and microorganisms

Corrosion in oilfield operations often occurs through complex synergistic mechanisms involving CO2, H2S, and microbiologically influenced corrosion (MIC), necessitating multifunctional mitigation strategies. In this study, a new bactericidal corrosion inhibitor, designated SS-41ABAC, was synthesized under laboratory conditions by combining SS-41A and benzalkonium chloride (BAC) in a 4 : 1 ratio. The SS-41A inhibitor was synthesized based on sodium sulfonate and aminoethyl ethanolamine at room temperature for 1–2 hours. This formulation integrates the film-forming properties of the sulfonate-based inhibitor with the antimicrobial activity of benzalkonium chloride, resulting in a multifunctional inhibitor with both corrosion protection and bactericidal effects. Laboratory evaluations were conducted across a range of concentrations to assess protective performance against CO2 and H2S corrosion using standardized electrochemical techniques. At 150 mg/L, SS-41ABAC achieved 98.3% inhibition efficiency against CO2 corrosion and 96% against H2S corrosion. Microbiological assays demonstrated complete (100%) suppression of sulfate-reducing bacteria (SRB), iron-oxidizing bacteria (FeOB), and acidproducing bacteria (APB) at the same dosage. The dual-action efficacy, combined with favorable physicochemical characteristics, positions SS-41ABAC as a promising candidate for integrated corrosion management in oil and gas production systems, particularly under conditions where conventional single-function inhibitors are insufficient.