Enhancement of A Cationic Surfactant by Capping Nanoparticles: Synthesis, Characterization and Multiple Applications

Area of Science:

• Materials Science
• Microbiology
• Corrosion Engineering

Background:

• Limited data exists on cationic surfactants' efficacy against oilfield Slime-Forming Bacteria (SFB) and their corrosion inhibition properties.
• SFB pose significant challenges in oilfield operations, necessitating effective biocidal and corrosion control strategies.

Purpose of the Study:

• To synthesize a novel cationic surfactant (CS) and enhance its properties by capping with zinc (ZnNPs-C-CS), manganese (MnNPs-C-CS), and tin (SnNPs-C-CS) nanoparticles.
• To evaluate the synthesized compounds as biocides and corrosion inhibitors against SFB, particularly *Pseudomonas* sp., and in saline environments.

Main Methods:

• Synthesis and characterization of the cationic surfactant using FTIR and NMR spectroscopy.
• Synthesis and characterization of metal nanoparticles (Zn, Mn, Sn) and their subsequent capping with the CS.
• Antimicrobial susceptibility testing against standard strains and *Pseudomonas* sp. (SFB), biofilm inhibition assays, and corrosion inhibition tests in 3.5% NaCl.

Main Results:

• CS-capped nanoparticles exhibited broad-spectrum antimicrobial and anti-biofilm activity at lower MICs, MBCs, MFCs, and MBICs, with efficacy in the order SnNPs-C-CS > MnNPs-C-CS > ZnNPs-C-CS > CS.
• ZnNPs-C-CS, MnNPs-C-CS, and SnNPs-C-CS demonstrated significant biocidal and corrosion inhibition effects against *Pseudomonas* sp. at 3.5% NaCl.
• Corrosion inhibition efficiencies reached 96.9% for SnNPs-C-CS, surpassing the CS efficiency of 85.7%.

Conclusions:

• The newly synthesized cationic surfactant, when capped with metal nanoparticles, shows enhanced antimicrobial and anti-corrosion properties.
• These enhanced compounds are effective biocides against slime-forming bacteria and corrosion inhibitors in high-salinity oilfield conditions.