Moshira Y. El-Awady

The Preparation and Characterization of Some Novel Quaternary Iminium Salts Based on Schiff-base as a Corrosion Inhibitor

Abstract Novel quaternary iminium compounds, namely, N-(4-methoxybenzylidene)-N-benzyldodecyliminium chloride (Ia), N-(4-methoxybenzylidene)-N-benzylhexadecyl iminium chloride (Ib), N-(4-methoxybenzylidene)-N-benzyloctadecyliminium chloride (Ic), and N-benzylidene-N-benzyldodecyliminium chloride, were prepared. The surface properties such as surface and interfacial tension, foaming, and emulsifying power of these surfactants were investigated. The surface parameters including critical micelle concentration (CMC), maximum surface excess (Γmax), minimum surface area (Amin), efficiency (PC20), and effectiveness (πCMC) were calculated. Free energy of micellization (ΔG°mic) and adsorption (ΔG°ads) were calculated.

Electrical and Gravimetric Estimation of the Corrosion Inhibition of Three Synthesized Cationic Surfactants N-(3-(Butylidene Amino) Propyl)-N, N-Dimethyl Alkan-1-Ammonium Bromide Derivatives in 1 M HCl

The inhibiting effect of three synthesized corrosion inhibitors that are based on Schiff base and named N-(3-(butylidene amino) propyl)-N,N-dimethyl decan-1-ammonium bromide, N-(3-(butylidene amino) propyl)-N,N-dimethyl dodecan-1-ammomium bromide, and N-(3-(butylidene amino) propyl)-N,N-dimethyl hexadecan-1-ammonium on the corrosion rate of mild steel in 1.0 M hydrochloric acid was monitored through gravimetric and electrochemical techniques at 25°C. The temperature effect ranging from 25°C to 70°C on the corrosion rate has been studied and used for predicting the adsorption isotherm and thermodynamic parameters. The propensity of the synthesized compounds to adsorb on the steel surface were found to obey Villamil adsorption isotherm. The inhibition efficiency was increased concurrently with a plethora of inhibitor concentration and a rise of the solution temperature. Polarization curves prove that the tested compounds act as mixed-type inhibitors. Double-layer capacitances of inhibitors decrease when compared to the blank solution.