المؤلفون: Sakhnenko, M. (Mykola), Karakurkchi, A. (Ann), Galak, A. (Alexander), Menshov, S. (Sergey), Matykin, O. (Oleksii)

المصدر: Eastern-European Journal of Enterprise Technologies

مصطلحات موضوعية: catalyst, titanium oxides, oxide coatings, plasma-electrolytic oxidizing, catalytic activity, UDC 621.35: 620.1, каталізатор, оксиди титану, оксидні покриви, плазмово-електролітичне оксидування, каталітична активність, катализатор, оксиды титана, оксидные покрытия, плазменно-электролитическое оксидирование, каталитическая активность, Indonesia

الوصف: We proposed a composition of citrate-pyrophosphate electrolytes with the addition of sulfates of iron triad metals for the formation of mixed oxide systems with the varied content of dopants. The introduction of an additional ligand contributes to an increase in the stability, operation period of working solutions and to the more uniform distribution of metals-dopants. The range of voltages for the single-stage plasma-electrolytic oxidizing of titanium alloys BT1-0 and OT4-1 is 120–160 V. As a result of oxidizing, we obtained metal-oxide systems TiOx·MOy (M=Fe, Co, Ni), which, depending on the nature of a dopant, have different types of surface structures. The largest content of dopant and the minimum size of the grain are characteristic of the cobalt-containing coatings. A potential possibility of obtaining the mixed oxide systems TiOx·(FeCoNi)Oy on the alloy OT4-1 is shown. We examined the dependences of spark voltage and the rate of change in the interelectrode voltage on the concentration of dopants in electrolyte. It was established that the formed mixed oxide coatings of titanium with the iron triad metals possess significant corrosion resistance; the highest value is inherent to the systems based on cobalt. It is shown that the incorporation of iron triad metals into the composition of oxide layers leads to an increase in the degree of surface development. This ensures an increase in the catalytic activity in the reactions of carbon mono-oxide oxidation. The obtained materials of varied thickness and morphology might be used in the technological systems of catalytic purification of natural and technogenic toxicants.

وصف الملف: application/pdf

العلاقة: https://www.neliti.com/publications/307101/examining-the-formation-and-properties-of-tio2-oxide-coatings-with-metals-of-iroTest

الإتاحة: https://www.neliti.com/publications/307101/examining-the-formation-and-properties-of-tio2-oxide-coatings-with-metals-of-iroTest

المؤلفون: Karakurkchi, A. (Ann), Sakhnenko, M. (Mykola), Ved, M. (Maryna), Galak, A. (Alexander), Petrukhin, S. (Serhii)

المصدر: Eastern-European Journal of Enterprise Technologies

مصطلحات موضوعية: ecological catalysis, oxide-metallic catalyst, plasma-electrolytic oxidation, catalytic activity, UDC 542.973 + 621.35, экологический катализ, оксидно-металлический катализатор, плазменно-электролитическое оксидирование, каталитическая активность, екологічний каталіз, оксидно-металевий каталізатор, плазмово-електролітичне оксидування, каталітична активність, Indonesia

الوصف: It is shown that a promising technique for obtaining oxide-metallic catalysts is the plasma-electrolytic oxidation (PEO) of valve metals, particularly aluminum and titanium alloys. Such a mode of synthesis makes it possible to form catalytically active materials with a developed surface, high content of dopants, and a broad scope of application over a single-stage technological process. The d-metals, in particular, manganese and cobalt are most promising as the dopants for oxide-metallic catalysts.Employing results of the experimental studies, we demonstrated pathways to control the composition and degree of surface development of the mangan- and cobalt-containing oxide-metallic systems by using complex electrolytes. It is established that the obtained oxide coatings are characterized by high catalytic activity in the model conversion reactions of carbon (II) oxide. In terms of such critical process parameters as the degree of conversion and ignition temperature, they are not inferior to, and in some cases, outperform industrial platinum catalysts. The use of manganese-containing oxide-metallic coating of the piston in an internal combustion engine leads to lower fuel consumption and a reduction in the toxicity of gas emissions

وصف الملف: application/pdf

العلاقة: https://www.neliti.com/publications/307336/application-of-oxide-metallic-catalysts-on-valve-metals-for-ecological-catalysisTest

الإتاحة: https://www.neliti.com/publications/307336/application-of-oxide-metallic-catalysts-on-valve-metals-for-ecological-catalysisTest

المؤلفون: Sakhnenko, N. (Nikolay), Ved, M. (Maryna), Karakurkchi, A. (Ann), Galak, A. (Alexander)

المصدر: Eastern-European Journal of Enterprise Technologies

مصطلحات موضوعية: the VT1–0 alloy, plasma electrolytic oxidation, oxide coatings, manganese, catalytic activity, UDC 621.35: 620.1, сплав ВТ1–0, плазменно-электролитическое оксидирование, оксидные покрытия, марганец, каталитическая активность, плазмово-електролітичне оксидування, оксидні покриви, манган, каталітична активність, Indonesia

الوصف: The study has substantiated the choice of components of manganese–containing electrolytes and their rational concentrations as well as determined the current density range for one–step plasma electrolytic oxidation of the VT1–0 alloy. Oxidation with mixed oxides produced coatings of different compositions and surface morphology. It has been shown that control over the chemical and phase compositions of coatings, the surface topography, and the grain size as well as incorporation of manganese oxides into a coating can be achieved by varying the concentration of the electrolyte and the oxidation parameters.Adding manganese sulfate to a pyrophosphate electrolyte has proved to be valuable for enhancing the content of the alloying component in the oxide layer and for reducing the concentrations of potassium and impurities. An increase in the current density of plasma electrolytic oxidation has been found to promote the formation of the oxide layer with a more developed surface area that is characterized by alternating torus–like inclusions and nanoporous sections. By studying the distribution of the content elements throughout the thickness of the oxide coating, it has been determined that manganese is uniformly distributed in the surface layer, but phosphorus is mainly located at the oxide–solution interface.It has been found that the synthesized mixed oxide coatings of manganese and titanium are highly resistant to abrasion. Incorporation of manganese has proved to reduce the grain size and improve the surface development, which facilitates catalytic activities in the oxidation reactions of carbon monoxide. The resulting materials can be used in process systems of catalytic purification.

وصف الملف: application/pdf

العلاقة: https://www.neliti.com/publications/306664/a-study-of-synthesis-and-properties-of-manganese-containing-oxide-coatings-on-alTest

الإتاحة: https://www.neliti.com/publications/306664/a-study-of-synthesis-and-properties-of-manganese-containing-oxide-coatings-on-alTest