Mechanistic and kinetic insight into catalytic oxidation process of heavy oil in in-situ combustion process using copper (Ⅱ) stearate as oil soluble catalyst

In this study, copper (Ⅱ) stearate was proposed as oil-soluble catalysts for catalyzing heavy oil oxidation in in-situ combustion (ISC) process to improve the efficiency of ISC for heavy oil recovery. Its catalytic mechanism and kinetics were deeply investigated by joint use of TG-FTIR, autoclave experiments, FESEM-EDX, and XPS, etc., together with isoconversional kinetic methods. We find that the addition of copper (Ⅱ) stearate initiated both efficient homogenous and heterogenous catalytic oxidation/combustion process of heavy oil. In low-temperature range, copper (Ⅱ) stearate (before its full decomposition) played a homogenous catalytic role in low temperature oxidation (LTO), and in high-temperature range, in-situ formed CuO nanoparticles (after the full decomposition of copper (Ⅱ) stearate) played a heterogenous catalytic role in the formation and combustion process of fuel (coke-like residues) in fuel deposition (FD) and high temperature oxidation (HTO) stages. Specifically, the addition of copper (Ⅱ) stearate significantly reduced the values of Eα of all reaction stages (LTO, FD, and HTO), especially at the later stage of LTO, FD and the beginning of HTO (the maximum values of Eα were decreased from about 500–600 KJ/mol to 300–400 KJ/mol), decreased the energy required to overcome reaction barriers, and improved the formation rate and quality of coke-like residues, which thus promotes the formation of coke-like residues and their combustion a more continuous process. Such a superior catalytic effect makes copper (Ⅱ) stearate have a great potential in improving efficiency of ISC process for heavy oil recovery

ELECTRICAL PROPERTIES OF TITANIUM NITRIDE FILMS SYNTHESIZED BY REACTIVE MAGNETRON SPUTTERING

259-259A use of the four-probe resistance measurements as a tool for characterization of a quality of titanium nitride thin films deposited by the reactive dc magnetron sputtering will be discussed in the report. Few series of ~ 50 nm thick films on various substrates as fused silica, monocrystalline silicon and magnesium oxide have been deposited with several degrees of freedom (substrate temperature, magnetron chamber atmosphere and working pressure etc.) varied in a wide range. Electrical resistivity correlation with the films properties will be reported

Epitaxial thin-film Pd<inf>1-x</inf>Fe<inf> x</inf> alloy: a tunable ferromagnet for superconducting spintronics

© 2020, Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature. Thin epitaxial films of the palladium-rich Pd1−xFex alloy were synthesized and extensively studied as a tunable ferromagnetic material for superconducting spintronics. The (001)-oriented MgO single-crystal substrate and the composition range of x = 0.01–0.07 were chosen to support the epitaxial growth and provide the films with magnetic properties spanning from very soft ferromagnet for memory applications to intermediately soft and moderately hard for the programmable logic and circuit biasing, respectively. Dependences of the saturation magnetization, Curie temperature and three magnetic anisotropy constants on the iron content x were obtained for the first time from the analyses of the magnetometry and ferromagnetic resonance data. The experimental results were discussed based on existing theories of dilute ferromagnetic alloys. Simulation of the hysteresis loops within the Stoner-Wohlfarth model indicates the predominant coherent magnetic moment rotation at cryogenic temperatures. The obtained results were compiled in a database of magnetic properties of a palladium-iron alloy in a single-crystal thin-film form considered as a material for superconducting spintronics

Structure Features of the Nanocrystalline Ni Films Formed by Ion Sputtering Technique

Abstract: Thin nanocrystalline Ni films with a thickness of ~340–360 nm are synthesized by ion sputtering on single crystal Si(111) substrates under high vacuum conditions. X-ray diffraction, scanning electron microscopy with microanalysis, vibration magnetometry and differential thermomagnetic analysis are used to study structure, magnetic phase composition, and magnetic properties of the initial and thermally annealed Ni films. It is found that, under certain deposition modes, the initial nickel films at room temperature have a saturation magnetization by an order of magnitude lower than that of nickel, and after thermal annealing at a temperature of 723 K, they exhibit magnetic anisotropy perpendicular to the surface. It is shown that the reduced value of the saturation magnetization is associated with a significant (3%) tensile deformation of the crystal lattice of nickel. It is found that the perpendicular magnetic anisotropy in the annealed films is due to the presence of tensile macro-stresses because of the differences in the thermal expansion coefficients of the film and the substrate

Oxidation of Petroleum Asphaltenes Coupled with Iodination

© 2020, Springer Science+Business Media, LLC, part of Springer Nature. Oxidation of petroleum asphaltenes by potassium iodide (KI) is described. Oxidation under mild conditions is shown to be accompanied by iodination of the asphaltene aromatic core. The inducing reaction is the oxidation of sulfide sulfur atoms in the asphaltenes with reduction of iodate anion to molecular iodine; the coupled reaction, electrophilic substitution. X-ray photoelectron spectroscopy detected an increase in the mass fraction of oxygen as compared with the initial sample and formation of C–I bonds. IR spectroscopy found that oxidation of the asphaltenes is accompanied by the formation of carboxyl and sulfoxide groups. Raman spectroscopy revealed a decrease in the size of the oxidized asphaltene molecules as compared to the native asphaltenes. X-ray powder diffraction analysis showed a decrease in the interplanar spacing of the asphaltene oxidation product that was due to ordering and a denser arrangement of the aliphatic fragments

Single-stage plasma-chemical synthesis and characterization of carbon nanoparticle-polymer suspensions

© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim A thin-film styrene polymer–carbon nanoparticle composite was obtained in a single-stage alternating current dielectric barrier discharge plasma-chemical process. The allotropic forms of the carbon nanoparticle filler were traced by transmission electron microscopy (TEM). TEM revealed an extraordinary adhesive encapsulation of the carbon nanoparticles by the polymer. It was found that the corona discharge regime provides an onion-like carbon filler that enhances the mechanical strength and chemical resistance of the synthesized polymer–carbon nanoparticle film. Measurements of the electrical properties of the films implicitly confirmed the uniformity of the carbon filler distribution

Metallo-Supramolecular Coordination Polymers Based on Amidopyridine Derivatives of Pillar[5]arene and Cu(II) and Pd(II) Cations: Synthesis and Recognition of Nitroaromatic Compounds

Decasubstituted pillar[5]arenes containing amidopyridine fragments have been synthesized for the first time. As was shown by UV-vis spectroscopy, the pillar[5]arenes with p-amidopyridine fragments form supramolecular associates with Cu(II) and Pd(II) cations in methanol in a 2:1 ratio. Using a sol-gel approach these associates are transformed into metallo-supramolecular coordination polymers (supramolecular gels) which were characterized as amorphous powders by scanning electron microscopy (SEM) and dynamic light scattering (DLS). The powders are able to selectively adsorb up to 46% of nitrophenols from water and were incorporated into an electrochemical sensor to selectively recognize them in aqueous acidic solution