Synthesis and Evaluation of New Poly Cationic Surfactants as Corrosion Inhibitors for Carbon Steel in Formation Water

TWO new polycationic surfactants abbreviated as (PTEAA.10 and PTEAA.12) were prepared by homopolymerization of triethanolamine acrylate monomer followed by quaternization with 1- bromodecane and 1-bromododecane. FT-IR, H-1-(CNMR)-C-13, and GPC have been used to confirm the chemical structure of the prepared surfactants. The prepared polycationic surfactants have been tested as corrosion inhibitors for carbon steel X65 in formation water. Weight loss, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization accompanied by SEM and EDX techniques were used to study the inhibition performance of PTEAA.10 and PTEAA.12. The prepared polymeric cationic surfactants act as mixed type inhibitors according to Tafel data. The inhibition efficiency of PTEAA.12 at 250 ppm was 92.8 %. The inhibition action was attributed to the formation of the adsorbed layer of surfactants over X65 surface that was follow Langmuir adsorption isotherm. The resistance of the adsorbed layer (R-ct) was a function in concentration and hydrophobicity of the surfactants.