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1.
ACS Omega ; 9(14): 16842-16850, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38617663

RESUMO

The current work aims to synthesize new amphipathic compounds, TGHA and PGHA, and investigate their demulsification performance (DP) in water-in-crude oil emulsions. Their chemical structures, thermal stability, interfacial activity, and micelle formation were investigated by different techniques. The bottle test method was used to investigate the effect of demulsifier concentration, water content, temperature, and demulsification time (DT) on the DP of TGHA and PGHA compared to a commercial demulsifier (CD). The results indicated that these parameters have a noticeable impact on the DP of TGHA and PGHA. The results also showed that TGHA exhibited higher DP than PGHA at all investigated parameters, which could be explained by increasing its hydrophobicity due to lower oxyethylene units in its structure than PGHA. An increase in these units means increased hydrophilicity, which led to obstruction of PGHA molecule diffusion in crude oil as a continuous phase. Moreover, TGHA gave a comparable DP with CD, as it gave a higher DP and shorter DT than CD at a higher water content (50%), while the latter achieved the highest DP and the shortest DT at a low water content (10%).

2.
ACS Omega ; 9(12): 13746-13763, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38560005

RESUMO

The study aims to synthesize two green pyrazole compounds, N-((1H-pyrazol-1-yl)methyl)-4-nitroaniline (L4) and ethyl 5-methyl-1-(((4-nitrophenyl)amino)methyl)-1H-pyrazole-3-carboxylate (L6), and test their action as corrosion inhibitors for carbon steel (CS) in a 1 M HCl solution. Both chemical and electrochemical methods, namely, gravimetric measurements (WL), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS), were used to assess the efficiency of the investigated molecules. DFT calculations at B3LYP/6-31++G (d, p) and molecular dynamics simulation were used to carry out quantum chemical calculations in order to link their electronic characteristics with the findings of experiments. The organic products exhibited good anticorrosion ability, with maximum inhibition efficiencies (IE %) of 91.8 and 90.8% for 10-3 M L6 and L4, respectively. In accordance with PDP outcomes, L6 and L4 inhibitors act as mixed-type inhibitors. Assessment of the temperature influence evinces that both L4 and L6 are chemisorbed on CS. The adsorption of L4 and L6 on CS appears to follow the Langmuir isotherm. Scanning electron microscopy and UV-visible disclose the constitution of a barrier layer, limiting the accessibility of corrosive species to the CS surface. Theoretical studies were performed to support the results derived from experimental techniques (WL, PDP, and EIS).

3.
ACS Omega ; 8(46): 43955-43963, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38027311

RESUMO

This work deals with poly(ethylene terephthalate) waste as a precursor to synthesize new cross-linked poly(ionic liquids) (CLPILs). The newly synthesized CLPILs, VPCT-Cl and VPCT-AA, were used for magnetite nanoparticle surface modification, producing VCL/Fe3O4 and VAA/Fe3O4, respectively. The chemical structures of the CLPILs and surface-modified Fe3O4 were elucidated by Fourier transform infrared and X-ray diffraction. Additionally, the particle size, zeta potential (ζ), contact angle, and magnetic properties of VCL/Fe3O4 and VAA/Fe3O4 were investigated using different techniques. Furthermore, the performance of these nanoparticles for oil spill cleanup was evaluated using various influencing factors, e.g., the contact time and the Fe3O4/crude oil ratio. VCL/Fe3O4 and VAA/Fe3O4 showed excellent performance in oil spill cleanup. The data showed that the performance increased with the contact time and the Fe3O4 ratio. Furthermore, the reusability of VCL/Fe3O4 and VAA/Fe3O4 over four cycles was also explored. The reusability data indicated that reused VCL/Fe3O4 and VAA/Fe3O4 showed promising performance in oil spill cleanup.

4.
ACS Omega ; 8(18): 16145-16157, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37179637

RESUMO

Bismuth ferrite (BiFeO3) is regarded as an important ABO3 perovskite in the areas of energy storage and electronics. A high-performance novel MgBiFeO3-NC nanomagnetic composite (MBFO-NC) electrode was prepared using a perovskite ABO3-inspired method as a supercapacitor for energy storage. The electrochemical behavior of the perovskite BiFeO3 has been enhanced by magnesium ion doping in the basic aquatic electrolyte as the A-site. H2-TPR revealed that the doping of Mg2+ ions at the Bi3+ sites minimizes the oxygen vacancy content and improves the electrochemical characteristics of MgBiFeO3-NC. Various techniques were used to confirm the phase, structure, surface, and magnetic properties of the MBFO-NC electrode. The prepared sample showed an enhanced mantic performance and specific area with an average nanoparticle size of ∼15 nm. The electrochemical behavior of the three-electrode system was shown by cyclic voltammetry to have a significant specific capacity of 2079.44 F/g at 30 mV/s in 5 M KOH electrolyte. GCD analysis at a 5 A/g current density also showed an enhanced capacity improvement of 2159.88 F/g, which is 3.4× higher than that of pristine BiFeO3. At the power density of 5284.83 W/kg, the constructed MBFO-NC//MBFO-NC symmetric cell showed an exceptional energy density of 730.04 W h/kg. The MBFO-NC//MBFO-NC symmetric cell was employed as a direct practical application of the electrode material to entirely brighten the laboratory panel, which had 31 LEDs. This work proposes the utilization of duplicate cell electrodes made of MBFO-NC//MBFO-NC in portable devices for daily use.

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