scholarly journals Thiocarbohydrazones Based on Adamantane and Ferrocene as Efficient Corrosion Inhibitors for Hydrochloric Acid Pickling of C-Steel

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1068
Author(s):  
Abdelwahed R. Sayed ◽  
Hany M. Abd El-Lateef

N′-(adamantan-2-ylidene)hydrazinecarbothiohydrazide and 2-(ferrocenyl-1-ylidene) hydrazinecarbothiohydrazide are used in coordination and organometallic complexes. The important idea of the research in this paper is the principal to prepare thiocarbohydrazones from the reaction of 2-acetylferrocene (Fe-Th) or 2-adamantanone (Ad-Th) with carbonothioic dihydrazide. The materials were elucidated by elemental analysis and spectral data. The as-prepared compounds were applied as effective corrosion inhibitors for HCl pickling of C-steel. Detailed investigations on electrochemical (open circuit potential (OCP) vs. time, potentiodynamic polarization (PDP), and impedance spectroscopy (EIS)) techniques and surface morphology studies are introduced in this work. Results indicated that Fe-Th could deliver greater inhibition performance than Ad-Th, and the highest protection capacity values of 93.6% (Ad-Th) and 97.9% (Fe-Th) were accomplished at 200 ppm. The adsorption of Ad-Th or Fe-Th additives followed the Langmuir isotherm with both the chemical and the physical adsorption with chemisorption predominance. EIS measurements supported a betterment in the capacitive behavior with the corrosion inhibitors. The inhibitors exhibited a mixed-type behavior as observed from the PDP studies. Field emission scanning electron microscopy (FESEM) and Fourier-transform infrared spectroscopy (FTIR) studies emphasize the occurrence of a protective layer of the as-synthesized organic inhibitors on the C-steel interface. Theoretical studies (density functional theory (DFT) calculations and Monte Carlo (MC) simulations) provide appropriate support for the experimental findings. The existing report provides very significant consequences in formulating and designing novel thiocarbohydrazone inhibitors with high protection efficacy.

Molecules ◽  
2019 ◽  
Vol 24 (1) ◽  
pp. 207 ◽  
Author(s):  
Nnaemeka Nnaji ◽  
Njemuwa Nwaji ◽  
John Mack ◽  
Tebello Nyokong

This study describes the adsorption behavior of organic inhibitors at the aluminum-HCl solution interface and their corrosion inhibition performance. The organic inhibitors employed are: 4-(benzo [d]thiazol-2ylthio)phthalonitrile (BTThio) and tetrakis[(benzo[d]thiazol-2-yl-thio)phthalo- cyaninato]gallium(III) chloride (ClGaBTThioPc). The corrosion behavior of these inhibitors is investigated using electrochemical and computational techniques. Open circuit potential results reveal predominant cathodic character for the mechanism of aluminum corrosion inhibition by the inhibitors. Inhibition efficiency values from potentiodynamic polarization measurements increase from 46.9 to 70.8% for BTThio and 59.7 to 81.0% for ClGaBTThioPc within the concentration range of 2 to 10 μM. Scanning electron microscopy (SEM) measurements reveal protection of the metal surface from acid attack, in the presence of the inhibitors and energy dispersive X-ray (EDX) measurements show that the most probable way by which the inhibitors protect the metal surface would be by shielding it from the corrosion attacks of Cl− from the acid. Quantum chemical parameters corroborate well with experimental findings.


Author(s):  
S Al-Baghdadi ◽  
T S Gaaz ◽  
A Al-Adili ◽  
A A Al-Amiery ◽  
M S Takriff

Abstract The University of Technology in Baghdad addresses problems related to the corrosion of metals. In the present investigation, a thiophene derivative, namely, 2-acetylthiophene thiosemicarbazone (2-AT), was synthesized and examined as a corrosion inhibitor for mild steel in a 1-M hydrochloric acid environment by using weight loss and scanning electron microscopic techniques. The inhibition efficiency of this inhibitor increases with increase in concentration, which offered an inhibition efficiency up to 96%. It was found that the inhibition efficiency decreases with long immersion time. The temperature effect on the inhibition performance was studied at various immersion times and revealed that the inhibition efficiency decreases with increasing temperature. The adsorption of the inhibitor on the surface of mild steel in the corrosive environment followed the Langmuir isotherm. The results of scanning electron microscopy (SEM) reveal that the 2-AT molecules confirmed the presence of a protective layer on the surface of a mild steel sample. The density-functional theory as a quantum modeling technique which is used to study the electronic structure reveals that the obtained findings were found to be consistent with the experimental results.


Author(s):  
Sehrish Habib ◽  
Eman Fayyed ◽  
Muddasir Nawaz ◽  
Adnan Khan ◽  
Abdul Shakoor ◽  
...  

Corrosion results in considerable materials and equipment failure. According to one survey, about 1/4 to 1/3 of the total interruption in industries is due to detrimental effects of corrosion. It is, therefore, important to prevent corrosion to guarantee the reliability of the assets. The present work is aimed to explore the purpose of CeO2 as a carrier for corrosion inhibitors and its capability to release inhibitors, to achieve decent corrosion protection efficiency in epoxy-based polymeric nanocomposite coatings. Amine-based corrosion inhibitors (N-methylthiourea NMTU and Dodecylamine DDA) were used for CeO2 nano container modification, and corrosion inhibition efficiency has been explored utilizing electrochemical impedance spectroscopy (EIS) in 3.5 wt% NaCl solution. Loading of inhibitor into nanocontainer has been confirmed through Fouriertransform infrared spectroscopy (FTIR) and Brunauer-Emmett-Teller (BET). It was observed that 25% and 29.75% w/w of NMTU and DDA were loaded into nanocontainers, confirmed through Thermogravimetric analysis (TGA). Scanning electron microscopy (SEM) analysis endorsed the formation of a protective layer on a scratch area to protect steel from the external environment. This protective layer played a very important role in protecting steel from progressing corrosion on the defect site from the aggressiveness of the solution. EIS measurements revealed the decent corrosion inhibition efficiency of these inhibitors in order of DDA>NMTU. As a result, they are a favorable solution for longer endurance of coated piping steel and decreased operation expense contributing to economic savings, materials reliability and safety.


2018 ◽  
Vol 1 (2) ◽  
pp. 43
Author(s):  
Farid Wajdi ◽  
Saprizal Hadisaputra ◽  
Iwan Sumarlan

The corrosion inhibition performance of benzimidazole and its derivatives have been studied by density functional theory DFT in aqueous medium. For this investigation, the corrosion inhibition efficiencies of the protonated and non-protonated spesies of benzimidazole and its derivatives were investigated. The ionization potential of the inhibitors has a strong influence on the efficiency of corrosion inhibitors. The linear correlation was shown between electronic properties and corrosion inhibition efficiency. Electron donating substituents increase the corrosion inhibition efficiency, whereas electron withdrawing substituents give the opposite effect. The NH2 substituent contributes highest, whereas NO2 provides the weakest contribution to the corrosion inhibition efficiency for both non-protonated and protonated species of inhibitors. 


2018 ◽  
Vol 2 (9) ◽  
pp. 1674-1691 ◽  
Author(s):  
Sourav Kr. Saha ◽  
Priyabrata Banerjee

The purposeful incorporation of aliphatic, branched chain and substituted aromatic moieties in the molecular skeleton of organic Schiff bases, in line with corrosion inhibition performance, has been conducted.


Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2275
Author(s):  
Arafat Toghan ◽  
Mohamed Gouda ◽  
Kamal Shalabi ◽  
Hany M. Abd El-Lateef

Converting low-cost bio-plant residuals into high-value reusable nanomaterials such as microcrystalline cellulose is an important technological and environmental challenge. In this report, nanocrystalline cellulose (NCC) was prepared by acid hydrolysis of macrocrystalline cellulose (CEL). The newly synthesized nanomaterials were fully characterized using spectroscopic and microscopic techniques including FE-SEM, FT-IR, TEM, Raman spectroscopy, and BET surface area. Morphological portrayal showed the rod-shaped structure for NCC with an average diameter of 10–25 nm in thickness as well as length 100–200 nm. The BET surface area of pure CEL and NCC was found to be 10.41 and 27 m2/g, respectively. The comparative protection capacity of natural polymers CEL and NCC towards improving the SS316 alloy corrosion resistance has been assessed during the acid pickling process by electrochemical (OCP, PDP, and EIS), and weight loss (WL) measurements. The outcomes attained from the various empirical methods were matched and exhibited that the protective efficacy of these polymers augmented with the upsurge in dose in this order CEL (93.1%) < NCC (96.3%). The examined polymers display mixed-corrosion inhibition type features by hindering the active centers on the metal interface, and their adsorption followed the Langmuir isotherm model. Surface morphology analyses by SEM reinforced the adsorption of polymers on the metal substrate. The Density Functional Theory (DFT) parameters were intended and exhibited the anti-corrosive characteristics of CEL and NCC polymers. A Monte Carlo (MC) simulation study revealed that CEL and NCC polymers are resolutely adsorbed on the SS316 alloy surface and forming a powerful adsorbed protective layer.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
E. S. Kozlyakova ◽  
A. V. Moskin ◽  
P. S. Berdonosov ◽  
V. V. Gapontsev ◽  
S. V. Streltsov ◽  
...  

AbstractUniform quasi-one-dimensional integer spin compounds are of interest as a potential realization of the Haldane conjecture of a gapped spin liquid. This phase, however, has to compete with magnetic anisotropy and long-range ordered phases, the implementation of which depends on the ratio of interchain J′ and intrachain J exchange interactions and both uniaxial D and rhombic E single-ion anisotropies. Strontium nickel selenite chloride, Sr2Ni(SeO3)2Cl2, is a spin-1 chain system which passes through a correlations regime at Tmax ~ 12 K to long-range order at TN = 6 K. Under external magnetic field it experiences the sequence of spin-flop at Bc1 = 9.0 T and spin-flip transitions Bc2 = 23.7 T prior to full saturation at Bsat = 31.0 T. Density functional theory provides values of the main exchange interactions and uniaxial anisotropy which corroborate the experimental findings. The values of J′/J = 0.083 and D/J = 0.357 place this compound into a hitherto unoccupied sector of the Sakai-Takahashi phase diagram.


Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 274
Author(s):  
Alexander V. Smolin ◽  
Мikhail N. Mikhailov ◽  
Aleksey F. Gadzaov ◽  
Leonid M. Kustov

The problem of identifying correlations between catalytic and electrocatalytic processes is one of the fundamental problems of catalysis among “simple” organic substances, and the oxidation of CO and rCO2 is of great interest, since CO and CO2 are considered in pairs both during catalytic and electrocatalytic transformations. In the case of electrocatalysis, this analysis is important in the study of fuel cells. In this paper, we studied the correlation between the oxidation of reduced forms of CO2 (rCO2) under potentiodynamic-galvanoctatic electrochemical and open-circuit conditions of measurements on polycrystalline (pc)Pt in H2CO3. Periodic oscillations are revealed at the oxidation of Had and rCO2 on (pc)Pt. Quantum chemical calculations were carried out on the Pt13 cluster in order to identify the mechanisms of the rCO2 oxidation reaction. The correspondence in the energy parameters of the oxidation process of rCO2 under open-circuit conditions and electrochemical conditions is shown. The preliminary analysis of the system using density functional (DFT) calculations is carried out and the most stable systems that are based on Pt13 are found, namely rOH-Pt13-(CO)n, rOH-Pt13-(COH) and rOH-Pt13-(rCOOH). OH• species was chosen as the most likely candidate for the role of the oxidant for rCO2. Preliminary calculations for the expected reactions were carried out, and the optimal PES is revealed.


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