Investigations of non-ionic surfactants derived from triazoles and pyrroles as potent corrosion inhibitors for carbon steel in hydrochloric acid

Abstract

The effectiveness of two synthetic non-ionic surfactants (NIS), including triazole and pyrrole derivatives, to inhibit corrosion of C-steel in 1.0 M HCl solution was tested. Their chemical compositions were verified using some of the analytical data. All of the synthesized compounds displayed good surface activity when different surface coefficients were tested. The corrosion parameters were determined employing chemical and electrochemical methods. The surface features of these compounds were identified. The anticorrosion efficacy (AE%) rises with rising the concentration of NIS compounds and with reducing temperature, surface and interfacial tension, and critical micelle concentration. The EIS diagram showed that as the concentration of NIS compounds increased, charge transfer resistance raised and double-layer capacitance reduced due to its adsorption of on the C-Steel surface. The values of AEPDP %. reached 89.98% and 91.45% at 500 ppm of compounds A and B, respectively by applying the polarization method. The anti-corrosion process was explained by the formation of adsorbed film that separated the C-steel surface from the corrosive HCl solution. The adsorption is subjected to Freundlich isotherm. The two NIS compounds functioned as mixed-type inhibitors, as revealed by potentiodynamic polarization. Some surface characteristics. were identified and emphasized the anticorrosive effect of two NIS compounds