Cationic Gemini Surfactant as a Corrosion Inhibitor and a Biocide for High Salinity Sulfidogenic Bacteria Originating from an Oil-Field Water Tank

A novel cationic gemini surfactant (NCGS) was synthesized and characterized. The inhibitory effect of NCGS was evaluated on the basis of protecting a metal surface from the salinity (5.49 % NaCl) and the activity of environmental sulfidogenic bacteria which originated from an oil-field water tank. Sulfidogenic bacterial activities were determined based on sulfide production, redox potential, changes in biofilm structures and constituents and metal corrosion rate calculations. At high surfactant concentrations, the sulfide production was completely inhibited as well as a considerable drop in the redox potential was observed in the reactor’s bulk phase. A minimum inhibitory concentration of the NCGS was achieved at a concentration of 1 mM. The NCGS showed a high ability to inhibit a biofilm over the metal surface at a concentration of 0.1 mM. The lowest metal corrosion rate was detected at a concentration of 5 mM with a metal corrosion inhibition efficiency of 97 %. In addition the NCGS showed a nonspecific biocidal activity against Gram-positive and Gram-negative bacterial strains.