Excellent Inhibition Efficiency Research Articles

Facile preparation of multifunctional cellulose nanocrystals from coffee residue via hydrothermal technique: Prolific roles on the water purification, antibacterial and antifungal applications

In this work, the facile preparation of coffee residue (CR)-derived multifunctional cellulose nanocrystals (CNCs) via hydrothermal technique has been successfully attempted. The morphological structure, functionality, crystalline pattern, surface chemistry, elemental content and surface charge were evaluated. The adsorptive property was assessed using both anionic and cationic aqueous pollutants, chlorpyrifos and methylene blue (MB), and simulated by the non-linear isotherm models and kinetic equations. Its unique antibacterial and antifungal functions were tested against both gram-negative/positive bacterial and fungal species. The particle length and diameter, aspect ratio, crystallinity index, sulfate group content and zeta potential of this newly prepared rod-shaped CNCs were identified to be 432.39 nm, 23.57 nm, 18.34, 75.0 %, 0.21 mmol/g and −32.7 mV, respectively. CR-CNCs recorded an outstanding adsorptive feature for both MB and chlorpyrifos, with the monolayer adsorption capacities of 403.02 mg/g and 159.75 mg/g, respectively. The adsorptive uptakes could be effectively preserved via solvent regeneration technique, even after 5 adsorption-desorption runs. Excellent inhibition efficiencies against both gram-negative/gram-positive bacteria, and fungal species have been detected, with the growth-inhibition zones ranging from 10.9 to 26.7 mm. The novel protective roles of the newly prepared CR-CNCs against both biological and water contaminants have been well-elucidated.

Electrochemicaland Computational insightsinto the utilization of an N-heteroaromatic containing compound2-(4-Methoxy-phenyl)-5-naphthalen-2-yl-[1,3,4]oxadiazole as a promising anticorrosive agent for mild steel in corrosive medium

In this investigation,the corrosion inhibition properties of an N-heteroaromatic containing compound 2-(4-Methoxy-phenyl)-5-naphthalen-2-yl-[1,3,4]oxadiazole (MPNO), against mild steel (MS) in 1M HCl using various analytical techniques have been examined. This study included weight-loss measurements at different temperatures (303-323K), electrochemical analyses using Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP), and surface morphology investigations with Scanning Electron Microscopy (SEM). The experimental results demonstrated that MPNO exhibited excellent corrosion inhibition efficiency of 85.53% at a minimal 400ppm inhibitor concentration with a mixed-type inhibition mechanism, as evidenced by the charge transfer resistance (RCT) value of 327.02 Ω.cm2 derived from the EIS analysis. Additionally, the analysis of quantum chemical descriptors revealed EHOMO (-8.6335 eV), ELUMO (-1.0277 eV), energy gap (ΔE = 7.60 eV), dipole moment (µ = 2.618 D), indicating inhibitor capability to acquire electrons and donate them to the metal's vacant d-orbitals, thus enhancing its adsorption activity and inhibitory properties. The density functional theory (DFT) computational studies complemented the experimental findings and provided a deeper understanding of the interaction modes between the inhibitors and the MS surface.

Lawsonia inermis as an Active Corrosion Inhibitor for Mild Steel in Hydrochloric Acid

Corrosion is a pervasive issue affecting metallic materials, with significant economic losses and safety risks in various industries. Mild steel, extensively used in construction and infrastructure, faces corrosion challenges, needing continuous research to effectively tackle them. Natural compounds, because of their eco-friendliness and corrosion inhibition potential, are attracting increasing interest for corrosion control. Lawsonia inermis (LI), or henna, a plant native to North Africa and South Asia, has bioactive compounds exhibiting corrosion inhibitive properties. This study comprehensively explores Lawsonia inermis’s effectiveness as a corrosion inhibitor for mild steel, filling a gap in the existing research. Various concentrations of Lawsonia inermis extract were tested in acidic solutions to evaluate corrosion inhibition. Experimental results indicate a significant reduction in the corrosion rate with increasing inhibitor concentration. Langmuir adsorption isothermal analyses reveal the adsorption mechanism as being an interplay between physisorption and weak chemisorption. Electrochemical measurements demonstrate Lawsonia inermis’s capability to alter both cathodic and anodic reactions, leading to improved corrosion resistance. Scanning electron microscopy reveals a more even surface morphology in the presence of the Lawsonia inermis, indicating corrosion inhibition. Gas chromatography–mass spectrometry (GC-MS) analyses identified organic compounds in Lawsonia inermis extract responsible for corrosion inhibition. Overall, Lawsonia inermis emerges as a promising corrosion inhibitor for mild steel, offering excellent inhibition efficiencies. This study sheds light on its adsorption behaviour and provides insights into its mechanism of action. These findings underscore Lawsonia inermis’s potential as a green corrosion inhibitor, paving the way for its practical application in industrial corrosion protection strategies.

Excellent corrosion inhibition efficiency of Catharanthus roseus (Nayantara or Sadabahar) leaf aqueous extract on mild steel in chloride-contaminated solutions at different pH

The efficacy of Catharanthus roseus (Nayantara or Sadabahar) leaf extract as a green corrosion inhibitor for mild steel in chloride-contaminated environments has been investigated in the present work. This study has employed a straightforward, practical, and less expensive Maceration process to prepare leaf extract. The adaptability of the extract as a corrosion inhibitor has been evaluated through electrochemical polarization and impedance studies in chloride-contaminated environments with varying pH levels. In addition, long-term corrosion monitoring has been conducted to evaluate the sustainability of the inhibitor against chloride-induced corrosion at a neutral pH level. This novel study has revealed that the extract defends mild steel against chloride assaults better at pH 2 than it does in neutral or alkaline conditions. Moreover, electrochemical studies and subsequent characterizations have confirmed the film-forming nature of the inhibitor.

تحضير وتقييم بوليمرات رخيصة كمضادات للبكتريا ،الاكسدة ومثبطات تاكل لسبيكة من نوع N80 في تركيز 0.1N من حامض الفسفوريك

في هذا العمل ، تم تحضير بولي بوتادين (PBD) من نفايات الاطارات . وطعم البولي بوتادين المهلجن باستخدام أحادي وثنائي وثلاثي إيثانول امين ، ودرس التطعيم عن طريق حيود الأشعة السينية والمسح المجهري الإلكتروني. وتشير الخواص الحرارية (TGA, DSC) إلى أن المركبات المحضرة تمتلك ثابتًا حرارياً حتى 202 درجة مئوية. باستخدام تقنيات الاستقطاب الديناميكي الفعال ، تم قياس تأثيرات الامتزاز والتآكل للبوليمرات الثلاثة المطعمة على فولاذ N80 في.0.1N H3PO4 في اربع درجات حرارية مختلفة : 25 و 35 و 45 و 55 درجة مئوية. وقد اظهرت البوليمرات المحضرة كفاءة تثبيط ممتازة عند درجات الحرارة المختلفة. يعتبر pBut-g-mono ethanol amine هو الأكثر فعالية كمثبط للتآكل في جميع درجات الحرارة المختبرة. كما ان سلوك الامتزاز للبوليمرات الثلاث تخضع لمخطط لانجموير ، وقيم الطاقة الحرة المتحصلة توضح ان الامتزاز الذي يحدث على سطح N80هو من النوع المختلط كما تشير منحنيات تافل إلى أن البوليمرات المختبرة تعمل كمثبطات أنوديك وكاثودية مختلطة. من ناحية أخرى ،وجد أن جميع البوليمرات المحورة أظهرت خصائص متميزة كمضادة للأكسدة وللبكتيريا.

Role of acrylate terpolymers in flow assurance studies of crude oil

Paraffinic crude oil causes deposition in the pipeline at low temperatures which hinders the flow during pipeline transportation. The primary technique for mitigation of paraffin deposition is chemical treatment. Polymeric chemical additives have gained considerable attention as flow improvers for waxy crude oil. Terpolymer application for flow assurance is a novel approach since terpolymers are seldom used as chemical additives for crude oil. Current research aims to synthesize four acrylate terpolymers with different alkyl pendant chains and study their effect on the rheological behavior of crude oil. The structure of additives was validated and their depression effect was investigated. The results of the investigation revealed that the additives showed significant decrease in pour point (ΔPP = 21 °C for CO-1 and 15 °C for CO-2) at a dose of 1000 ppm for CO-1 and 2000 ppm for CO-2. These results were also supported by rheological data which exhibited a significant reduction in viscosity (>75%) of both the crude oils which showed the efficiency of additives as flow improvers. Moreover, the cold finger test displayed excellent paraffin inhibition efficiency of synthesized additives (66 and 52% for CO-1 and CO-2, respectively). The investigation demonstrated a promising role of terpolymers as flow improvers for waxy crude oil.

Development of a facile one-pot synthesized fluorescent green polyesters as cooling water antiscalants for industrial application

Currently, antiscalants used in cooling water are expected to be environmental-friendly, good scale inhibitive, fluorescence tracing, and industrial-friendly. Aliphatic biodegradable photoluminescent polymers (BPLPs) synthesized from citric acid, aliphatic diols, and various amino acids are fluorescent polymers containing heteroatom six-membered conjugated ring chromophores. Their cross-linked BPLPs have potential for use as implant or device materials, and vivo bioimaging probes. However, so far, no one has found that BPLPs can be used as efficient antiscalants for cooling water. In this work, we demonstrate a facile one-pot microwave-assisted synthesis of BPLPs from cost-effective materials. The products were characterized by Fourier transforms infrared spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopy, gel permeation chromatography, and fluorescence spectroscopy. Thus prepared BPLPs can be directly used as a novel type green fluorescent antiscalant without further purification. They have an excellent calcium phosphate inhibition efficiency that can reach 98.6 % with a dosage of 25 mg·L−1 in the static scale inhibition test at 80 °C.

Theoretical Investigation of New Possible Fatty Hydrazides Corrosion Inhibitors Via Density Functional Theory

In this study, two new possible corrosion inhibitors derived from fatty hydrazides were investigated via the density functional theory (DFT) to measure the quantum chemical calculation of these new molecules and analyse their corrosion inhibition ability. The quantum calculation parameters included the calculation for the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) and the energy gap between HOMO and LUMO. Other chemical descriptors were also measured, including the global hardness, electronegativity, and the fraction of transferred electrons. The results revealed that both new possible corrosion inhibitors, TADHS11 and TADHS12, showed excellent chemical reactivity and inhibition efficiency based on the calculation of electronic properties, with band gap energy of 4.35 eV for TADHS10 and 4.18 eV for TADHS11. The other chemical descriptor also revealed similar observations, which agree that these two compounds exhibit excellent corrosion inhibitor properties. Overall, all data were consistent with previously reported findings, proving the ability of these new possible fatty hydrazide derivatives as effective corrosion inhibitors.

Experimental and computational studies on the corrosion inhibition potential of a novel synthesized thiophene and pyridine-based 1,3,4-oxadiazole hybrid against mild steel corrosion in 1 N HCl.

A convenient synthesis of a novel 1,3,4-oxadiazole derivative, specifically known as, 2-(5-methylthiophen-2-yl)-5-(pyridin-3-yl)-1,3,4-oxadiazole (MTPO), is reported along with a comprehensive evaluation of its ability to inhibit the corrosion of mild steel (MS) in a 1 N HCl environment using weight loss, EIS, PDP, SEM, EDX, and UV-Vis spectroscopy. The investigated inhibitor expressed excellent inhibition efficiency (99.05% at 500ppm, 298K) with a mixed-type inhibitory mechanism as demonstrated by the PDP technique. Furthermore, MTPO followed Langmuir adsorption isotherm, which provides insights into the adsorption phenomena, demonstrating that it exhibits superior adsorption behavior on the MS surface compared. In silico investigations, using DFT computation and MD simulation complements the experimental outcomes revealing strong adsorbing attributes of the MTPO hybrid with the ω - and ω + values of 8.8882eV and 4.4787eV, respectively. In addition, the radial distribution function also addressed the chemisorption behavior of MTPO. This article also takes into consideration the various ways in which the inhibitor interacts with the mild steel, offering potential insights for developing strategies to mitigate metal dissolution in acidic environments.

Soybean and Glycine as Potential Corrosion Inhibitors for Steel in Hydrochloric Acid: Electrochemical and Morphological Studies

The potential of soybean and glycine as organic corrosion inhibitors for steel in acid solution was examined through weight loss tests and potentiodynamic polarization. Both soybean and glycine were characterized via FTIR and UV-visible. The result shows that the soybean and glycine contain isoflavone and nitrogen bonds respectively as a beneficial element in inhibiting the corrosion of steel. Corrosion tests were performed with and without the presence of soybean and glycine for 3 days of immersion in the acidic medium. Corrosion inhibition efficiency measured via electrochemical test found that both soybean and glycine give an excellent corrosion inhibition efficiency at 1.5 g/L in 0.5 M HCl up to 96% and 94% respectively. Tafel analysis reveals both inhibitors perform mixed types inhibitors which predominantly anodic inhibition. Pseudo-passivation was observed in the Tafel curve indicating the capabilities of both inhibitors to passivate the corrosion at anodic potential. Observation of the steel samples through an optical microscope shows that the corrosion of the steel surface was inhibited in the addition of soybean and glycine in HCl. The roughness of the steel surface affected by the combination of uniform and pitting corrosion was also reduced. In overall, soybean and glycine exhibit excellent anticorrosive properties due to the presence of significant chemical structures and active functional groups. Analysis of the inhibition mechanism through isotherm showed that soybean and glycine followed Langmuir isotherm, indicating the adsorption type for both inhibitors is chemisorption. The results obtained from this study could be a good reference in diversifying the study of amino acids as metal corrosion inhibitors to benefit metal-based industries.

Fluorine-free, robust and self-healing superhydrophobic surfaces with anticorrosion and antibacterial performances

Superhydrophobic surfaces with water-repelling ability have important applications, such as self-cleaning, antibacterial and corrosion protection. However, the using of harmful fluorinated materials and its poor mechanochemical stability limit its practical application. Herein, a fluorine-free, robust and self-healing superhydrophobic surface is prepared through a two-step method of laser processing and spraying coating for anticorrosion and antibacterial applications. Laser processing is used to construct periodic micron-sized pillars for obtaining strong interface bonding between coating and substrate by mechanical interlocking effect, and as an ‘armor’, preventing the removal of the coating. The coating consists of epoxy resin (EP), hexadecyltrimethoxysilane (HDTMS) and γ-aminopropyltriethoxysilane treated Cu2O (KH550-Cu2O). The superhydrophobic surface can withstand various mechanical durability tests, such as multiple sandpaper abrasion and tape peeling cycles. It exhibits excellent corrosion inhibition efficiency (ηp > 99 %) on Mg alloy, Tinplate and Al alloy, which results from superhydrophobicity and organic coating. The superhydrophobicity endows surface with excellent antibacterial adhesion performance in a static liquid environment. The bactericidal activity of KH550-Cu2O can effectively inactivate the bacteria in contact with the surface and the free bacteria, providing excellent antibacterial ability in a dynamic liquid environment. It still exhibits good anticorrosion and antibacterial abilities after multiple mechanical abrasion cycles due to the outstanding mechanical durability. Moreover, it exhibits outstanding self-healing ability to plasma etching and oil contamination, self-cleaning ability under air and oil conditions, and chemical stability against acids and alkalis solution. All the above excellent performances promote its application in a wider range of fields.

Superhydrophobic magnesium hydroxide layer with self-healing behavior and long-term anti-corrosion property via surface modification with insufficiently hydrolyzed silane

The long-term anti-corrosion of superhydrophobic materials is essential to its practical application, as well as the self-healing behavior which can significantly increase the lifetime of the superhydrophobic surfaces in corrosive environment. Magnesium hydroxide, as a non-toxic, eco-friendly, and low-cost material, has been applied to fabricate robust superhydrophobic layer through electrodeposition under the structure direction of xanthan gum in our reported works. In this work, we designed a method of fabricating superhydrophobic magnesium hydroxide layer with self-healing ability through a special silane modification method. 1H,1H,2H,2H-perfluorodecyltriethoxysilane was treated into a hybrid of both hydrolysate and amounts of unhydrolyzed small units. The remained unhydrolyzed units hydrolyzed during the corrosion process, and modified the exposed magnesium hydroxide again. In this way, the lifetime of the superhydrophobic surface is significantly prolonged (624 h). The prepared superhydrophobic magnesium layer also demonstrates excellent water repellency (contact angle, 157.33 ± 4.78°; sliding angle, 3.80 ± 1.05°), self-cleaning property, robustness (adhesion, 5B; linear abrasiveness, 2400 mm), and high inhibition efficiency (99.9991 %). This study put a foot further to the application of low-cost and eco-friendly superhydrophobic materials with long lifetime in the field of metal anti-corrosion.

Synergistic Gas Hydrate and Corrosion Inhibition Using Maleic Anhydride: N-Isopropylmethacrylamide Copolymer and Small Thiols.

Kinetic gas hydrate inhibitors (KHIs) are often used in combination with film-forming corrosion inhibitors (CIs) in oilfield production flow lines. However, CIs can be antagonistic to KHI performance. In this study, maleic anhydride-co-N-isopropylmethacrylamide copolymer (MA:NIPMAM) and its derivatives were successfully synthesized and tested for gas hydrate and corrosion inhibition. KHI slow constant cooling (1 °C/h) screening tests in high-pressure rocking cells with synthetic natural gas and CO2 corrosion bubble tests in brine were performed in this study. The results revealed that underivatized MA:NIPMAM in water (as maleic acid:NIPMAM copolymer) showed poor KHI performance, probably due to internal hydrogen bonding. However, derivatization of MA:NIPMAM with 3-(dibutylamino)-1-propylamine (DBAPA) to give MA:NIPMAM-DBAPA gave excellent gas hydrate inhibition performance but only weak corrosion inhibition performance. Unlike some KHI polymers, MA:NIPMAM-DBAPA was compatible with a classic fatty acid imidazoline CI, such that neither the KHI polymer performance nor the corrosion inhibition of the imidazoline was affected. Furthermore, excellent dual gas hydrate and corrosion inhibition was also achieved in blends of MA:NIPMAM-DBAPA with small thiol-based molecules. In particular, the addition of butyl thioglycolate not only gave excellent corrosion inhibition efficiency, better than adding the fatty imidazoline, but also enhanced the overall gas hydrate inhibition performance.

Synthesis, Characterization and evaluation of two organic compounds as corrosion inhibitors for carbon steel alloy (C1010) in acidic medium of 0.1M HCl.

In this study, 4-chlorobenzodithioatebenzyltrimethylammonium and 4-methoxylbenzodithioatebenzyltrimethylammonium were synthesized and characterized by 1H-NMR, FTIR, UV-Visible and Mass techniques. Then they evaluated as corrosion inhibitors for carbon steel alloy (C1010) against corrosive environment of hydrochloric acid at different concentrations at 25 ˚C. both inhibitors revealed an excellent inhibition efficiency (97.95) % and (97.13) % at optimal concentrations (9) ppm and (8) ppm respectively. The effect of temperature on the corrosion was studied in absence and presence of the inhibitor, the raising of temperature leads to reduce the efficiency of the inhibitor and CR was enhanced. On the other hand, kinetic parameters such as activation energy , enthalpy of activation , entropy of activation and Gibbs free energy of activation were calculated which are insisted a physical adsorbed behavior for the inhibitor, an endothermic corrosion reaction whether in presence or in absence of the inhibitor and enhanced non-spontaneous behavior in presence of the certain inhibitor. Each one of the inhibitor has the mixed inhibition behavior.

Fabrication of a fluorine-free photocatalytic superhydrophobic coating and its long-lasting anticorrosion and excellent antibacterial abilities

Superhydrophobic multifunctional coatings have wide application prospects in construction, shipping, transportation equipment and aerospace etc. In this paper, a fluorine-free photocatalytic superhydrophobic coating with long-lasting anticorrosion performance and excellent antibacterial ability has been developed on various substrates by a simple spraying method. The coating is mainly composed of epoxy resin (EP), polydimethylsiloxane (PDMS) and hydrophobically modified micron ZnO (m-ZnO) and nano ZnO (n-ZnO). The coating maintains excellent wettability to various common liquids, and the water contact angle (WCA) and sliding angle (SA) of coating are 162.8° and 3°, respectively. The synergistic effect of the air layers and the coating denseness endows coating with excellent corrosion inhibition efficiency (ηp > 99.9 %) in 3.5 wt% NaCl solution and neutral salt spray tests for 30 days. The photocatalytic activity and superhydrophobicity endow coating with bactericidal activity and antibacterial adhesion properties, thus providing the coating with excellent antibacterial ability in dynamic or static liquid environment. Furthermore, the coating can withstand chemical erosion, ultraviolet radiation and mechanical durability tests such as knife scraping, tape peeling and sandpaper wear cycles. This large-scale fabrication, environmentally benign, low cost and high performance coating has potential practical applications in a wider range of fields.

Effective corrosion inhibition of mild steel using novel 1,3,4-oxadiazole-pyridine hybrids: Synthesis, electrochemical, morphological, and computational insights

An easy synthesis of two 1,3,4-oxadiazole derivatives, namely, 2-phenyl-5-(pyridin-3-yl)-1,3,4-oxadiazole (POX) and 2-(4-methoxyphenyl)-5-(pyridin-3-yl)-1,3,4-oxadiazole (4-PMOX), and their corrosion-inhibition efficacy against mild steel corrosion in 1 N HCl, is evaluated using weight loss from 303 to 323 K, Electrochemical Impedance Spectroscopy (EIS), Potentiodynamic Polarization (PDP), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), UV–Vis spectroscopy, along with theoretical evaluation. Both POX and 4-PMOX exhibit excellent inhibition efficiency, with values reaching 97.83% and 98% at 500 ppm, respectively. The PDP analysis reveals that both derivatives act as mixed-type inhibitors. The Langmuir adsorption isotherm provides insights into the adsorption phenomena, demonstrating that 4-PMOX exhibits superior adsorption behavior on the mild steel surface compared to POX. This finding is further supported by SEM, DFT, RDF, and MSD analyses. Quantum mechanical parameters, including EHOMO, ELUMO, dipole moment (μ), energy gap (ΔE), etc., are in good agreement with the effectiveness of inhibition performance revealing ΔE values of 3.10 and 2.75 for POX and 4-PMOX, respectively. The results obtained from this study hold significant implications for researchers aiming to design more efficient organic inhibitors to combat metal corrosion.

A Review on The Inhibition Efficiency of Green Materials as a Potential Corrosion Protection on Ferrous and Non-Ferrous Metals in Various Environments

Greenmaterial is a beneficial material in combating corrosion on any metallic structure. Since it is a green material, hence it can be classified as an environmental friendly material. Environmental friendly material (eco-friendly) is the best material choice to be opted for corrosion mitigation. Eco-friendly materials produce no pollution to the environment, safe to be used because of organic materials, made from a waste product or a natural resource, cheap, wide range of availability, renewable resource, freeof heavy metals and free of toxic compounds. Therefore, numerous research studies have been done worldwide by researchers as to study the effectiveness in term of inhibition efficiency of the eco-friendly material as corrosion mitigation method. This review highlighted a few eco-friendly materials such as rice husk, egg shell, banana peel and henna that have been tested successfully in the previous research studies as corrosion prevention method. Many of related and relevant research articles to this review topic have been included as to review the inhibition efficiency of the eco-friendly materials in corrosion mitigation. The result showed that the inhibition efficiency for all green materials reviewed was mainly above 90%. This showed that the green materials acted as a remarkable material either as a direct corrosion inhibitor or incorporated into a coating. The corrosion rate on metal was decreased as the molecules of green material being absorbed on the metal surface, creating a protective barrier and protected the metal surface from corrosion attack. This review provided the significant and valuable information regarding the application of eco-friendly material as corrosion mitigation because the facts in this review have indicated that the eco-friendly materials have an excellent inhibition efficiency for corrosion protection purpose on different metals in various environments.

Benzethonium chloride as a tungsten corrosion inhibitor in neutral and alkaline media for the post-chemical mechanical planarization application

The cleaning solution for the post-chemical mechanical planarization (post-CMP) process of tungsten in neutral-alkaline media requires corrosion inhibitors as an additive, especially for advanced devices where the device node size shrinks below 10 nm. In the present study, the corrosion inhibition performance of benzethonium chloride (BTC) is evaluated in neutral-alkaline conditions. The electrochemical impedance spectroscopy (EIS) analysis showed ∼ 90 % of corrosion inhibition efficiency with an optimum concentration of 0.01 wt% BTC at both pH 7 and 11. Langmuir adsorption isotherm, frontier molecular orbital theory, molecular simulation, contact angle, precipitation study, and X-ray photoelectron spectroscopy analysis were performed to identify the inhibition mechanism of the BTC molecule on the W surface. Based on the proposed mechanism, the electrostatic attraction between the positively charged N atom in the BTC molecule and the negatively charged W surface initiates the adsorption of the molecule. The high dipole moment and large molecular size enhance the physical adsorption of the molecule to the surface. In addition to this, the adsorption isotherm analysis shows that possible chemical interaction with a moderate value of Gibbs free energy change of adsorption exists between the W and BTC molecule. The excellent corrosion inhibition efficiency of BTC on W is confirmed by the frontier molecular orbital theory and molecular dynamic simulation analysis.

Fructus cannabis protein extract powder as a green and high effective corrosion inhibitor for Q235 carbon steel in 1 M HCl solution

The Fructus cannabis protein extract powder (FP), was firstly used as a green and high effective corrosion inhibitor through a simple water-extraction method. The composition and surface property of FP were characterized by FTIR, LC/MS, UV, XPS, water contact angle and AFM force-curve measurements. Results indicate that FP contains multiply functional groups, such as NH, CO, CN, CO, etc. The adsorption of FP on the carbon steel surface makes it higher hydrophobicity and adhesion force. The corrosion inhibition performance of FP was researched by electrochemical impedance, polarization curve and differential capacitance curve. Moreover, the inhibitive stability of FP, and the effects of temperature and chloride ion on its inhibition property were also investigated. The above results indicate that the FP exhibits excellent corrosion inhibition efficiency (~98 %), and possesses certain long-term inhibitive stability with inhibition efficiency higher than 90 % after 240 h immersion in 1 M HCl solution. The high temperature brings about the FP desorption on the carbon steel surface, while high concentration of chloride ion facilitates the FP adsorption. The adsorption mechanism of FP follows the Langmuir isotherm adsorption. This work will provide an insight for protein as a green corrosion inhibitor.

Superior Long-Term Corrosion Inhibition of N80 Steel by New Eco-friendly Hydrazone-Based Compounds in a Simulated Oil Well Acidizing Environment: Establishing the Mechanism at the Molecular Level

The acid treatment process of production wells is one of the most acid-induced corrosive processes. Corrosion inhibitors are an effective tool to inhibit the acids employed in acidizing treatments. Herein, new eco-friendly hydrazone-based compounds, namely, 2-(4-isobutylphenyl)-N-((1E,2E)-3-phenylallylidene) propanehydrazide (IPP) and N'-cyclohexylidene-2-[4-(2-methylpropyl)phenyl] propanehydrazide (CIP), were prepared through the functionalization of ibuprofen (IBF) and applied for corrosion mitigation of N80 steel in 15 wt % HCl (referred to hereafter as blank). The anticorrosion performance of selected compounds was investigated by employing weight loss (WL), potentiodynamic polarization curves (PPCs), and electrochemical impedance spectroscopy (EIS), complemented by scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses. In addition, density functional theory-based tight-binding (DFTB) modeling was conducted to get molecular-level insights into inhibitor-metal bonding. Experimental results revealed excellent long-term corrosion inhibition efficiency at very low concentrations of inhibitors and a mixed-type inhibition process. Numerically, N80 steel polarization resistance increased from 5.51 Ω cm2 in blank to 608.4 and 396 Ω cm2 in blank inhibited with 5 × 10-3 mol/L of IPP and CIP, respectively, equivalent to 99% and 98% inhibition efficiency based on EIS experiments. Besides, SEM and AFM images showed that, after addition to 15 wt % HCl, inhibitors could effectively prevent the acid attack on the N80 steel surface. The fitting of experimental data to adsorption isotherms indicated that inhibitors' adsorption followed the Langmuir isotherm model and mixed physicochemical adsorption on the metal surface. The DFTB simulation revealed that inhibitor molecules can create covalent and physical interactions with iron atoms, which is further confirmed by partial density of states (PDOSs) analysis.