Jeenat Aslam

Study on the Inhibition of Mild Steel Corrosion by Cationic Gemini Surfactant in 1 M HCl

The cationic gemini surfactant 1,2-bis(N-tetradecyl-N,N-dimethylammonium)ethane dibromide (14-2-14) was synthesized using a previously described method. The surfactant was characterized using 1H NMR. The corrosion inhibition effect of 14-2-14 on mild steel in 1 M HCl at temperatures 30–60°C was studied using weight loss measurements, potentiodynamic polarization measurements and electrochemical impedance spectroscopy. Morphology of the corroded mild steel specimens was examined using scanning electron microscopy (SEM). The results of the studies show that gemini surfactant is an efficient inhibitor for mild steel corrosion in 1 M HCl; the maximum inhibition efficiency (IE) of 98.06% is observed at surfactant concentration of 100 ppm at 60°C. The %IE increases with the increasing inhibitor concentration and temperature. The adsorption of inhibitor on the mild steel surface obeys Langmuir adsorption isotherm. SEM studies confirmed smoother surface for inhibited mild steel specimen. GRAPHICAL ABSTRACT

Anti-corrosive properties of Poly(aniline-co-2,3-xylidine)/ZnO nanocomposite coating on low-carbon steel

Abstract A copolymer nanocomposite Poly(aniline-co-2,3-xylidine)/ZnO [Poly(AN-co-XY)/ZnO], pure copolymer and its homopolymers namely, Poly(aniline-co-2,3-xylidine) [Poly(AN-co-XY)], Polyaniline (PANi) and Poly (2,3-xylidine) were synthesized by chemical oxidative polymerization using ammonium persulfate as an oxidant in hydrochloric acid medium. The synthesized compounds were characterized by FTIR, XRD, SEM, and TEM techniques. Saturated solutions of the synthesized compounds were made in N-methyl-2-pyrrolidone and casted on low-carbon steel specimens using 10% epoxy resin as a binder. The anticorrosion behavior of polymeric coatings was studied in 3.5 wt% NaCl solution at a temperature of 30 °C by electrochemical techniques, which include: open-circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy. Protective properties of nanocomposite coating were also evaluated at different immersion times for an extended period of 60 days. Anticorrosion properties of nanocomposite coating were compared with parent copolymer and individual homoplymers. SEM photomicrographs of the coated surface showed that Poly(AN-co-XY)/ZnO nanocomposite coating is crack free, uniform, and compact, whereas, copolymer and homopolymer coatings have surface defects. The performance of the polymer coatings followed the order: Poly(AN-co-XY)/ZnO > Poly(AN-co-XY) > PANi > Poly(2,3-xylidine). The presence of ZnO nanoparticles in copolymer resulted in significant improvement in corrosion resistance and provided better barrier properties.

Sugar based N,N ′-didodecyl- N,N ′digluconamideethylenediamine gemini surfactant as corrosion inhibitor for mild steel in 3.5% NaCl solution-effect of synergistic KI additive

The inhibitory behaviour of non-ionic sugar based N,N′-didodecyl-N,N′-digluconamideethylenediamine gemini surfactant, designated as Glu(12)-2-Glu(12) on mild steel (MS) corrosion in 3.5% NaCl at 30–60 °C was explored using weight loss, PDP, EIS and SEM/EDAX/AFM techniques. The compound inhibited the corrosion of mild steel in 3.5% NaCl and the extent of inhibition was dependent on concentration and temperature. The inhibiting action of Glu(12)-2-Glu(12) is synergistically enhanced on addition of potassium iodide (KI) at all concentrations and temperatures. The inhibiting formulation comprising of 2.5 × 10−3 mM of Glu(12)-2-Glu(12) and 10 mM of KI exhibits an inhibition efficiency of 96.9% at 60 °C. Quantum chemical calculations and MD simulation were applied to analyze the experimental data and elucidate the adsorption behaviour and inhibition mechanism of inhibitors. MD simulation showed a nearly parallel or flat disposition for Glu(12)-2-Glu(12) molecules on the MS surface providing larger blocking area to prevent the metal surface from corrosion.

Assessment of glycine derivative N-benzylidine-2((2-oxo-2-(10H-phenothiazine-10yl)ethyl)amino) acetohydrazide as inhibitor for mild steel corrosion in 1 M HCl solution: electrochemical and theoretical approach

Abstract Corrosion is a severe challenge which restricts the use of mild steel (MS) in various application where it comes in contact with aggressive chemicals and conditions. In this regard, different inhibitors were chosen, but environment unfriendliness of such inhibitors is a primary cause of concern. In this study, we present the systematic investigation of an environmentally benign compound, a glycine derivative N-benzylidine-2((2-oxo-2-(10H-phenothiazine-10yl)ethyl)amino) acetohydrazide (BPAA), as potential corrosion inhibitor at different temperature (30, 40, 50, and 60 °C). The investigation is accomplished by using the techniques including electrochemical polarization, electrochemical impedance spectroscopy (EIS), gravimetric, UV-visible spectrophotometry, FT-IR spectroscopy. The morphological characterization of the samples has been done by using high resolution SEM. The evaluated compound works as effective inhibitor for acid corrosion at substantially lower concentration and its adsorption on the MS surface was found to followed the Langmuir adsorption isotherm. Calculated thermodynamic parameters for adsorption unveiled a strong interaction amongst the inhibitor-MS surface. The electrochemical results revealed that the inhibitor act as mixed-type. The corrosion inhibition efficiency (IE) of the inhibitor was synergistically enhanced in the presence of surfactant additives sodium dodecyl sulfate and cetyl pyridinium chloride at quite lower concentration and showed that the addition of surfactant is an alternate strategy to enhance the IE and reduce the cost. The order of IE acquired from experimental results is successfully verified by theoretical calculations.