Weight Loss Techniques Research Articles

Sputtering yield and induced contamination of Kapton, PEEK and PTFE under xenon ions bombardment

Abstract In this article, we present the results of sputtering yield measurements of Kapton, PEEK and PTFE due to xenon ions bombardment. We measured these yield using the weight loss technique, for energies ranging from \qtyrange[range-units = single]{350}{800}{\eV} and incidence angles from \qtyrange[range-units = single]{0}{75}{\degree}. Polymers sputtering yield dependence versus incidence angle appears to be much lower than what we usually observe on other materials (such as metals). Furthermore, PTFE exhibits a very high erosion rate, which is two orders of magnitude bigger than Kapton and PEEK one. We also performed collection measurements using a quartz crystal microbalance (QCM) apparatus. Such method provides differential sputtering yields data which are key pieces of information regarding satellites contamination issues. We also computed the total sputtering yields obtained by this second method, and it appeared that they were much smaller than the ones measured previously by weight loss, specially for PTFE. This suggests that erosion products may be of different types (atoms, molecules) which are not all able to stick on a facing surface.

Lannea microcarpa Leaves Extract as Corrosion Inhibitor for Aluminium Metal in Acid Medium

Techniques for weight loss, electrochemistry, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were used to investigate the inhibitory impact of Lannea microcarpa leaves extract. The weight loss data showed that the plant extract's ability to suppress corrosion increased with higher concentrations and decreased with higher temperatures and HCl acid concentrations. According to the electrochemical data, the plant extract uses a mixed type mechanism to limit both cathodic and anodic reaction rates. Calculated activation energies were found to be higher in inhibited systems than in uninhibited systems, indicating physisorption, while negative values of ∆G point to a process that is both possible and spontaneous. The inhibitory mechanism was demonstrated by FTIR spectra to be an adsorption process through the functional groups present in the phytochemicals of the plant extract onto the surface of Al metal. SEM surface morphology study demonstrated the protection that the extract provided on the metal surface. Compared to other isotherm models that were examined, the adsorption data were found to be more reliable and suited the Langmuir isotherm well.

Terminalia bellirica fruit shell extract by microwave assisted extraction as a green inhibitor for mild steel acid corrosion: insight from chemical, electrochemical and computational studies

In the current study, the corrosion protection role of ethanol extract of Terminalia bellirica fruit shell on Mild Steel (MS) in 0.5 M HCl solution was studied by using weight loss, Tafel plot, AC impedance and surface techniques. The existence of functional groups in the plant extract was confirmed with the aid of FT-IR spectroscopy technique. The presence of 31.12% of gallic acid in the Terminalia bellirica fruit shell extract was complemented with HPLC and LCMS results. The surface coverage and protection efficiency of Terminalia bellirica fruit shell extract were enhanced with its concentration and declined with solution temperature. The activation parameters such as activation enthalpy, entropy and change in Gibb’s free energy are related to adsorption process were calculated and discussed. The adsorption of Terminalia bellirica fruit shell extract was found to obey the Langmuir adsorption model. The process of adsorption of inhibitor molecules on the metal surface can be verified by using UV–Visible spectroscopy technique. The potentiodynamic polarization and impedance results suggest that, Terminalia bellirica fruit shell extract functioned by adsorption at metal (MS)-Corrodent (0.5 M HCl) interface, which blocks the both cathodic and anodic half reactions of the MS corrosion process. Theoretical approach by Monte Carlo (MC) simulations and quantum chemical study support the experimental findings and adsorption of extract of Terminalia bellirica fruit shell molecules on MS surface.

Carob fruit extract as naturally products corrosion inhibitor for copper-nickel alloys in brine solutions

Copper-nickel alloys are the preferred material for desalination facilities and condensers and heat exchangers that use saltwater as a coolant. The eco-friendly compounds especially Carob fruit extract (CFE) has emerged as excessive green corrosion inhibitor for alloys. Cu-Ni alloys are widely used in various industries due to their excellent corrosion resistance. However, their performance can be compromised in aggressive environments like seawater (which is approximately 3.5% NaCl). To evaluate the corrosion behavior of these alloys and the effectiveness of corrosion inhibitors, researchers often employ weight loss, potentiodynamic polarization, and impedance spectroscopy techniques. The results showed that CFE exhibited a good ability to decrease the CR of alloys in 3.5% NaCl solution. The inhibition efficacy (IE) was reached to 92.6% and ̴ 83.2% at 300 ppm dose of CFE for Cu-10Ni alloy and Cu-30Ni alloy, respectively. The CR increases with temperature rising, but the addition of CFE reduces the CR, and the reduction depends on the dose of the extract. Adsorption of the extract gives a good fit to Langmuir, Temkin, and Freundlich isotherms model. The free adsorption energies of CFE on Cu-10Ni and Cu-30Ni alloys were 17.61 and 15.86 kJ mol−1, respectively, suggesting that CFE was weakly held to both alloys. The presence of a protective film on the alloys surface is confirmed by using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy and atomic force microscope (AFM). The study suggests that utilizing affordable, natural substances as green corrosion inhibitors presents a new strategy for promoting both resource efficiency and environmental sustainability.

Predictive Modeling and Adsorption Behavior, Kinetics, and Thermodynamic Studies of <i>Anthocleista grandiflora </i>Leaf Extract for Corrosion Inhibition of Carbon Steel in Seawater

This study investigates the corrosion inhibition performance of Anthocleista grandiflora leaf (AGL) extract on carbon steel in seawater, considering the effects of temperature, immersion time, and inhibitor concentration. Predictive modeling, adsorption behavior, and the kinetics and thermodynamics of the inhibition process were examined. The weight loss technique,characterization techniques combined with response surface methodology (RSM), revealed that the AGL extract follows the Langmuir adsorption model, exhibiting physical adsorption with ΔG values between −16.24 to −15.49kJ/mol, indicating spontaneous and endothermic inhibition. The thermodynamic parameters entropy (−198.87 to −52.58 J/mol), enthalpy (20.42 to 53.42 kJ/mol), and activation energy (13.68 to 56.32 kJ/mol further support this. The corrosion reaction follows first-order kinetics, with the half-life decreasing as the rate constant and extract concentration increase.The SEM images revealed that the AGL extract formed a protective surface layer on the mild steel, effectively preventing pitting. This protective effect became more pronounced as the concentration of the extract increased. RSM optimization identified optimal conditions for maximum inhibition efficiency (98.70%) and corrosion rate (0.058 mm/y) at 800 ppm, 303 K, and 45 days, with a prediction accuracy of 95%, making it suitable for application in the oil and gas industry.

Ruta graveolens Plant Extract as a Green Corrosion Inhibitor for 304 SS in 1 M HCl: Experimental and Theoretical Studies

This study evaluated the corrosion inhibitory effects of Ruta graveolens leaf extract for 304 stainless steel in 1 M HCl. The analysis of the leaf extract using HPLC indicated that the primary compounds present in the leaf extract were rutin, caffeic acid, p-coumaric acid, and apigenin. The inhibition efficiency (IE%) of the extract was studied using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and computational simulation (density functional theory, DFT). The effects of the inhibitor concentration and solution temperature were investigated. The results indicated that the IE% increased for increasing concentrations of the extract, while the reverse was true with increasing temperatures. At 25 °C and a 600 ppm extract concentration, the results indicated a maximum inhibition efficiency of 95%, 98%, and 96% by weight loss, potentiodynamic polarization, and EIS techniques, respectively. SEM observations showed a significant change in the surface morphology of the 304 SS with and without the addition of the inhibitor compound. At all temperatures, the adsorption of the inhibitor components onto the 304 SS surface was found to follow the Langmuir isotherm model, and the inhibition process was governed by physical adsorption. Furthermore, chemical interactions between the inhibitor and the 304 SS steel surface were elucidated via density functional theory (DFT) calculations.

Mango leaves extract as sustainable corrosion inhibitor for X70 steel in HCl medium: Integrated experimental analysis and computational electronic/atomic-scale simulation

Mangoes are one of the most abundant fruit tree crops in most countries. Unfortunately, mango leaves are generally dumped as agricultural waste due to their abundance, resulting in significant waste and environmental pollution. In this study, electrochemical and weight loss techniques were utilized to investigate the inhibitory mechanism of mango leaves extract (MLE) on the corrosion of X70 steel in 1 M HCl. The results indicated that MLE was an excellent corrosion inhibitor for X70 steel to resist corrosion in an acidic environment, and the inhibition efficiency was effectively improved by increasing the inhibitor concentration and decreasing the temperature. Electrochemical tests have shown that MLE functions as a corrosion inhibitor with a mixed-type mechanism. Fitting the adsorption isotherm with electrochemical data, confirmed that MLE demonstrates corrosion resistance on metal surfaces through adsorption, and this adsorption conforms to the Langmuir isotherm. The adsorption phenomenon was deeply investigated by using atomic force microscopy (AFM) and scanning electron microscopy (SEM). MLE is further proven to interact with the steel surface to generate an adsorption layer that prevents steel corrosion in an acidic environment. In particular, the density-functional tight-binding (DFTB) calculations results also suggest that the π electron and lone-pair electrons in the main components of MLE are conducive to enhancing the adsorption of corrosion inhibitor molecules on the iron surface, to achieve a more effective inhibition effect. Furthermore, the toxicity prediction indicates that the MLE components are nearly non-toxic, which complies with environmental protection regulations. MLE has excellent corrosion resistance, with a corrosion inhibition efficiency of nearly 90 % at a concentration of 400 mg/L, while also helping to solve agricultural waste management challenges.

Short-Term Changes in TNF-Alpha, IL-6 and Adiponectin Following Bariatric Surgery in Caucasian Obese Adults: An Observational Case-Control Study.

Background and Objectives: Overweight and obesity are well-known conditions that negatively impact the health and lifestyle of an individual. Bariatric surgery is one of the most efficient weight loss techniques. Besides the main effect on the bodyweight, improvement in the levels of inflammatory biomarkers, such as interleukin 6 (IL-6), tumor necrosis factor alpha (TNFalfa), and others, has been observed. The purpose of this study was to establish the correlations between obesity-linked chronic systemic inflammation (estimated with inflammatory cytokine levels) and the weight loss process after metabolic surgery. Materials and Methods: An observational cohort study included two categories: the patients with obesity-bariatric group and the patients without obesity-control group. The study was performed between 1 February 2021 and 1 March 2023. Baseline characteristics, anthropometrics, biochemical assessment and inflammatory biomarkers were measured both before surgery and one year after the procedure, in the case of the bariatric group. The control group was assessed in the same period as the pre-surgery bariatric group. The bariatric group underwent two types of bariatric procedures: the majority underwent laparoscopic sleeve gastrectomy whereas a select few underwent one anastomosis laparoscopic gastric bypass. Results: We performed a prospective study comprising 55 Caucasian patients-from which 33 patients had morbid obesity, a mean age of 41.76 ± 10.78 and a mean BMI of 43.34± 7.51 kg/m2. The preoperative levels of IL-6 were positively correlated with waist circumference (r = 0.354, p = 0.043), weight (r = 0.549, p = 0.001) and BMI (r = 0.520, p = 0.002). After applying the Kruskal-Wallis test and Dunn's test, significant differences for IL-6 (p = 0.010) and adiponectin (p = 0.024) were obtained for values recorded pre- and post-surgery. No correlation was found between adiponectin, IL-6, TNF- α levels and anthropometric indices after surgery. Our study showed that bariatric surgery significantly changes the values of inflammatory cytokines one year after surgery. Nevertheless, we did not find significant correlations between the baseline values of these inflammatory markers and the weight loss process after surgery at a short-term (one-year) follow-up. Conclusions: Our study demonstrated that bariatric surgery significantly changes the level of inflammatory cytokines one year after operation. We demonstrate that preoperative levels of IL-6 are positively correlated with age, WC, and BMI.

THE INHIBITIVE EFFECT OF THYMUS SERPYLLUM EXTRACT ON CORROSION OF STEEL

The study examined the inhibitive effect of thyme extract as a green inhibitor on the corrosion of two steel types, steel 1 - DC01 and steel 2 - X5 CrNi 18-10, in a 3% NaCl solution. Four test solutions were used: 1) blank 3% NaCl, 2) 3% NaCl + 0.5 g/L thyme extract, 3) 3% NaCl + 1.0 g/L thyme extract, and 4) 3% NaCl + 1.5 g/L thyme extract. Steel samples (3x3x0.2 cm) underwent chemical treatment before being exposed to the non-inhibited and inhibited solutions. Weight loss and electrochemical techniques, i.e. electrochemical impedance spectroscopy, were employed to investigate the corrosion rate and the inhibitive effect of thyme extract. All experiments were obtained on room temperature. After chemical treatment samples were immersed in blank and inhibited solutions for 2h, 4h, 6h, 8h, 24h, 48h и 168h. Based on the weight loss in steel samples for the time spent in prepared solutions, negative mass index of corrosion, Km - (g/m2h), depth corrosion indicator, π (mm/year), and degree of efficiency, protection factor, z (%), were calculated. The results of the gravimetric and electrochemical measurements showed that thyme extract had an inhibitive effect on the corrosion of the tested steels, but not sufficient to be recommended for commercial application. The average corrosion inhibition efficiency of thyme extract was below 60% for both steel types. For steel 1, the protection factor was above 80% only in solution 4 after 48h and 168h, while for steel 2, the protection factor was greater than 80% for all three inhibited solutions only after 168h. These findings suggest a very slow adsorption of phytochemicals from thyme extract on the surface of the tested steels.

Corrosion behaviour of superaustenitic stainless steel N08029 in harsh acidizing environment

It is vital to examine the resistance to corrosion of corrosion resistant alloys (CRAs) in severe oilfield corrosive environments such as acidizing to validate their performance. Super austenitic stainless steel (SASS) UNS N08029 was recently developed to offer competitive and improved corrosion resistance in extreme and aggressive environments. However, no systematic studies have evaluated the N08029 performance in acidizing conditions. In this study, N08029 was investigated in harsh acidizing conditions of different HCl concentrations (up to 25 % HCl), long immersion duration (up to 48 h), and at elevated temperatures (up to 80 °C) using both weight loss and electrochemical measurement techniques. Interestingly, all the test methods show that the corrosion resistance of the SASS increases with increasing the concentration of HCl acid. This may be due to the formation of ferric chloride protective layer on the steel surface after the dissolution of the formed chromium oxide layer by the increasing acid concentration. The decrease in the corrosion rate observed at higher HCl concentrations is because the higher concentration of HCl causes the more ferric chloride layer to form on the metal's surface. This layer protects the metal from further acid attack. Also, after 24 h immersion duration, a decrease in corrosion rate with further increase immersion duration was observed which may is also due to the formation of more ferric chloride protective layer. However, the corrosion resistant of the SASS was observed to decrease with increase in temperature of the test solution. The decreased resistance of the SASS to corrosion with increase in temperature is associated with the instability or damage of the passive/protective film on the surface of the SASS at elevated temperatures.

Exploration of UV-induced geometrical isomer-enriched Helichrysum kraussii extract as a corrosion inhibitor for Al(111) surface in 1.0 M hydrochloric acid: An experimental and theoretical study

This study evaluated UV-radiated Helichrysum kraussii (H. kraussii) extract for its corrosion inhibition on aluminium in 1.0 M HCl. To achieve this, techniques such as Liquid chromatography-mass spectrometry (LC-MS), Fourier transform infrared spectroscopy (FTIR), Gravimetric analysis, electrochemical analysis looking at electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP), contact angle and computational studies were used. The results obtained from these techniques made it possible to conclude the performance of UV-radiated H. kraussii as a corrosion inhibitor for aluminium metal. LC-MS and FTIR proved that the exposure of extract to UV radiation caused a change in the composition of extract metabolites, demonstrated by the increase in the number of peaks in the chromatogram and the shift in the FTIR spectrum. Weight loss technique showed that the extract inhibited the corrosion of aluminium with the maximum percentage inhibition of 84.6948 % at the concentration of 1500 ppm at 30 °C. The adsorption of the inhibitor molecules on the metal surface was found to obey the Langmuir adsorption isotherm, and the activation energy values proved that the adsorption mechanism was through physisorption. Nyquist plots semi-circles were found to increase with an increase in the extract concentration, showing an increase in the inhibition efficiency. Tafel's plot showed that both anodic and cathodic corrosion were inhibited. The DFT/PBE/GGA/DNP computational investigation obtained binding energies of the inhibitors on the aluminium surface that suggest that the Al···FA interaction happens through physical adsorption.

Corrosion resistance of aluminum against acid activation in 1.0 M HCl by symmetrical ball − type zinc phthalocyanine

The inhibition effect of symmetrical Ball − type Zinc Phthalocyanine on Aluminum in 1mol/L hydrochloric acid was analyzed by electrochemical techniques. A novel ball-type zinc phthalocyanine (Zn-Pc) inhibitor has been synthesized and verified utilizing FTIR, nuclear magnetic resonance (1H NMR and 13C NMR), MALDI-TOF MS, and absorption spectroscopy (UV-Vis). In addition, laser-induced breakdown and photoluminescence spectroscopy were employed for additional study. Weight loss technique was employed to investigate the corrosion inhibition effectiveness of the synthesized Zn-Pc on Aluminum in 1mol/L hydrochloric acid at the range of variation temperatures (293–333 K). The inhibition efficiency of Zn-Pc increased with higher concentrations of Zn-Pc and decreased as the temperature increased. Furthermore, Zn-Pc demonstrated outstanding outcomes, achieving 72.9% at a very low inhibitor concentration (0.4 mmol/L) at 298 K. The experimental data for Zn-Pc Aluminum in 1mol/L hydrochloric acid obeys the Langmuir adsorption isotherm. Moreover, the corrosion system’s thermodynamic parameters and activation energy were determined. Quantum chemical calculations applying the (DFT) Density Functional Theory method was conducted and applied in this study. These calculations played a pivotal role in elucidating molecular structures and reactivity patterns. Through DFT, numerous reactivity indicators were computed, providing valuable insights into the chemical behavior of the studied compounds. These indicators, such as frontier molecular orbitals, electron density, and molecular electrostatic potential, were subsequently correlated with experimental data.

Onion Peel Extract/Copper Oxide Nanoparticles as Corrosion Inhibitors for Carbon Steel in Hydrochloric Acid: Extraction, Characterization, Electrochemical Study, and Theoretical Explorations

The effectiveness of onion peel extract (OPE) as a corrosion inhibitor for carbon steel in a 1 M hydrochloric acid solution was investigated using weight loss (WL) techniques, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), and surface morphological examination. Additionally, this process was characterized by Fourier transform infrared (FT-IR) spectroscopy, energy dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), atomic force microscopy (AFM), and transmission electron microscopy (TEM). According to weight loss measurements, the protective efficiency of OPE increases with rising OPE concentration and decreases with increasing temperature of the corrosive solution. Polarization curves indicate that OPE acts as a mixed-type inhibitor in hydrochloric acid. The adsorption mechanism, supported by EIS results, shows that charge-transfer resistance increases and double-layer capacitance decreases with higher inhibitor concentration. The adherence of OPE to carbon steel follows the Langmuir isotherm, indicating a physical adsorption process, and the spontaneous adsorption of the inhibitor molecules is evidenced by the negative values of Gibb’s free energy of adsorption. The synergistic effect of copper oxide nanoparticles (CuO–NPs) in combination with OPE on the corrosion inhibition of carbon steel was also evaluated. The results demonstrated that the inhibition efficiency of OPE is enhanced in the presence of CuO–NPs due to synergistic interactions between OPE extract molecules and CuO–NPs. The electron-donating capacity of the chemical components in OPE was confirmed through theoretical studies employing quantum chemistry methods.

Bili leaf extract: Green corrosion inhibitor for zinc in hydrochloric acid-experimental and theoretical study

The primary goal of this study was to examine whether Bili leaf extract (BLE) (Aegle marmelos leaf) could inhibit zinc corrosion in an acidic environment, specifically in 0.05–0.10 M HCl solutions. The corrosion rate was examined using PDP (Potentiodynamic Polarization), EIS (Electrochemical Impedance Spectroscopy), and weight loss techniques. The research attains notable inhibition efficiencies of 99.0 %, 83.4 %, and 78.95 % in weight loss, PDP, and EIS respectively, at a concentration of 2.0 g/L BLE and a temperature of 303 K. The influence of temperature (ranging from 303 to 333 K) on the corrosion behaviour was examined upon the addition of BLE. As the concentration of BLE increased, the corrosion rate(CR) of Zn decreased, and a similar reduction was observed with decreasing temperature. Adsorption of BLE onto the metal surface followed by Langmuir and Freundlich adsorption isotherm models. The activation parameters of BLE and its negative Gibbs free energy indicate spontaneous adsorption rates. Tafel polarization measurements showed that BLE acts as a mixed-type corrosion inhibitor, meaning it influences anodic and cathodic reactions. FT-IR spectroscopy is employed to determine the functional groups of BLE. Atomic Force Microscopy(AFM)/Energy Dispersive X-ray (EDX)/Scanning Electron Microscopy (SEM) images of the zinc surface verified a significant reduction in surface inhomogeneities when BLE was present. The quantum parameters obtained through DFT(Density Functional Theory)/MD (Molecular Dynamics) demonstrated excellent agreement with the experimental findings.

Okra leaves extract as green corrosion inhibitor for steel in sulfuric acid: Gravimetric, electrochemical, and surface morphological investigations

Utilizing plant extracts as an alternative source for corrosion inhibitors holds significant promise in minimizing the risk of corrosion. In this study, an okra leaf extract (OLE) was employed as a corrosion inhibitor for N80 steel in 1.0 M H2SO4. The corrosion rate was assessed concerning temperature (30, 40, 50, and 60 °C) and inhibitor concentrations (blank, 25, 50, 75, and 100 ml/l) through weight loss and electrochemical polarization techniques. The results indicated that OLE functions as a mixed-type corrosion inhibitor, with corrosion rates increasing with temperature and decreasing with inhibitor concentration. The maximum corrosion inhibition efficiency reached 96 % at 30 °C and 100 ml/l. Adsorption studies revealed that OLE physically adsorbed onto the mild steel surface, following the Langmuir adsorption isotherm. Gravimetrical and electrochemical techniques were confirmed by FTIR and UV measurements, which showed the presence of a protective layer on the metal surface. Optical microscopy, AFM, and SEM images demonstrated the formation of a protective layer on the metal surface. Thermogravimetric analysis (TGA) highlighted the thermal stability exhibited by inhibitor molecules, which showed that OLE was thermally stable up to 85 °C.

Polyethyleneglycol bisphenol A epichlorohydrin copolymer (PEG-BEC) as a highly efficient inhibitor for mild steel corrosion in 1M HCl solutions

In this work, the corrosion inhibition performance of polyethyleneglycol bisphenol A epichlorohydrin copolymer (PEG-BEC) against mild steel in 1 M HCl was studied by electrochemical and weight loss techniques. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDAX) were applied to characterize the surface morphology of the mild steel samples. The corrosion mitigation efficiency was observed to rise as the concentration of PEG-BEC rises in the corrosive medium while increasing the temperature (25 °C -65 °C) resulting in a drop in the inhibition ability. Furthermore, under hydrodynamic conditions, the corrosion of the mild steel was found to deteriorate both in the absence and presence of PEG-BEC. Just with 10 ppm, an inhibition efficiency (IE) of 97.6% was obtained at 25 °C by EIS. PEG-BEC acts as a mixed-type inhibitor as observed by potentiodynamic polarization (PDP) technique. The observed corrosion inhibition action of PEG-BEC could be ascribed to the adsorption of the molecules and the formation of a protective film on the steel surface as evidenced by static water contact angle (WCA). Langmuir isotherm best describes the PEC-BEG-metal adsorption with large Kads values indicating a thermodynamically stable nature inhibition process. The obtained ∆G°ads = -35.138 to -39.522 kJ/mol indicate that the PEG-BEC spontaneously adsorbed onto the steel with strong tendency to provide protection to the mild steel surface via combination of chemisorption and physisorption processes. The ΔHads -53.07 kJ/mol and ΔSads= +0.048 kJ/mol-k, respectively, suggests an exothermic reaction accompanied by relatively increase in entropy of the PEG-BEC adsorption on the mild steel surface.

Study the Effect of “Di-dodecyl amine” as a Corrosion Inhibitor for Carbon Steel in HCl Medium

Numerous organic compounds have been investigated for their potential to reduce corrosion under various circumstances. This study investigated the effects of di-dodecyl amine, an organic chemical, on carbon steel metal corrosion at different temperatures while HCl acid was present. The examination was carried out using accepted methods for polarization, weight loss, and corrosion process testing. The obtained findings demonstrated that the corrosion rate reduces with increasing inhibitor concentration, leading to increased inhibition efficiency. Furthermore, as shown in the weight loss technique, the corrosion rate lowers with increasing surface coverage with organic inhibitor at 313 °C. In the anodic and cathodic polarization methods, as well as in the inhibition efficiency, it is observed to see the cathodic and anodic curves through which the occurrence of the potential and corrosion current is known. The current and corrosion potential decreases with increasing inhibitor concentration. The amines and methyl motiveless in this inhibitor's composition give it their efficacy since they may coat the metal surface and stop corrosion

Metronidazole mediated potassium iodide as high-performance deterioration retardant for mild steel in an acidic media

As corrosion scientists all over the world struggle to discover new metal deterioration retardant which can close the performance gap created by the legislative banned toxic inhibitors, we present in this research work an azole based drug and its mediation performance with a synergistic agent as ‘green’ metal degradation retardant. The anti-deterioration performance of the azole-based drug, metronidazole (MTN) and its different concentration combinations with potassium iodide (KI) were examined with materials degradation analysis tools such as functional group, nanoindentation, weight loss and electrochemical techniques. MTN alone performed well as an anti-deterioration retardant exhibiting retardation efficiencies (η%) in the range between 73 to 85% at different temperatures and analytical techniques. However, with the introduction of KI, an escalation in (η%) was obtained in the region of 92 to 97%. In addition, improved polarization resistance of chemical retardants on substrate cross sections was achieved, manifested by the resultant elevation in values of polarization resistances (Rp) from 1.54 Ω.cm2 of the blank to 30.61 Ω.cm2 of the optimum concentration, charge transfer resistances, (Rct) improved likewise from 6.03 to 144.07 Ω.cm2 and depreciation in the values of corrosion current densities (Icorr) from 8863.86 to 228.89 µA.cm2. This work describes a method of improving the metal deterioration retardation potentials of an azole compound, bringing out new knowledge on the degradation inhibition properties of MTN and the adsorption process taking place between the substrate and the belligerent environment. We hope it opens the door for the utilization of a mixture of MTN and KI as additives for the formulation of sealants, paints, conversion coatings and primers for ferrous alloys. It also encourages more investigations, to find additives such as suitable activating and accelerating agents for MTN to make It exercise the same or more anti-corrosion potents possessed by the banned hexavalent chromium (vi), benzothiazoles (BTA) and others. Some of these potents are the ability of MTN to function at a wide region of pH and in the moment of coating failure, what can enable an azole-containing coating, to undergo some chemical activities and still maintain the substrate surface integrity?

INVESTIGATION OF CORROSION INHIBITION POTENTIAL OF HYPHAENE THEBAICA SHELLS EXTRACT ON TANNERY MACHINES PARTS IN ACIDIC MEDIUM

Corrosion inhibition potential of ternary machine part was investigated by using ethanoic extract of hyphaene thebaica shells as inhibitor at different temperature of 313K and 333K. The Tannery machines part which are majorly made up of mild steels are subjected to harsh conditions, which include exposure to moisture, air, acid, base, salt and other environmental components that causes corrosion on machines’ parts. The aim of this research was to generate measurable and testable data towards the control of corrosion using plant (hyphaene thebaica shells ethanolic extracts) as inhibitor. This was accomplished through the determination of inhibitor’s performance by weight loss techniques, determination of metal-inhibitor interaction mechanism using kinetic parameters and adsorption isotherms (Langmuir and Temkin), the corrosion process through the use of exposure time, phytochemicals of the shell extracts, inhibitor concentration, media concentration, temperature, initial weight of metal and the weight of the metals in every 2 hours for a total of 6 hours. A weight loss technique was adopted and the weights of the mild steel were recorded every 2 hrs for 6 hrs. The highest inhibition efficiency (78.44%) was attained at 333 K for 0.1 g/dm3 concentration of the plant inhibitor. Inhibition efficiency decreased with further increase in the temperature. The green inhibitor was found to be effective because it is ecofriendly, inexpensive and biodegradable.

Corrosion Inhibition of Carbon Steel by Some Schiff Base Compounds in HCl and H2SO4 Solutions

AbstractThe inhibition power of two Schiff bases on carbon steel corrosion in 1 M HCl and 0.5 M H2SO4 solutions has been investigated using weight loss, Tafel polarization, and electrochemical impedance spectroscopy techniques. The results revealed that increasing the concentration of inhibitors in acidic solutions led to a higher inhibition efficiency. The polarization curves indicated that the Schiff bases acted as mixed inhibitors, affecting both the cathodic and anodic reactions. The adsorption of the inhibitors on the carbon steel surface followed the Langmuir adsorption isotherm, and various adsorption isotherm parameters such as Kads, ΔGads, ΔHads, and ΔSads were determined at room temperature. Furthermore, the effect of temperature on the inhibitors′ performance was examined within the range of 25–45 °C. The corrosion‐related activation energy, pre‐exponential factor (k), activation enthalpy, and entropy were calculated to assess the inhibitors′ behavior. Scanning electron microscopy (SEM) was employed to examine some carbon steel samples, revealing differences in inhibition efficiency attributed to the inhibitors′ chemical structure. The results highlighted the highest inhibition efficiency in H2SO4 medium at 93.4 %, with a corresponding free energy of 39.51 KJ/mol indicating physical‐chemical adsorption of inhibitor molecules. Furthermore, an enthalpy value of −40.6 KJ/mol suggested an exothermic inhibitor absorption process. The findings are presented and discussed in detail.