Carbon-Supported KCoMoS2 for Alcohol Synthesis from Synthesis Gas

KCoMoS2 was supported on various carbon support materials to study the support effect on synthesis gas conversion. Next to two activated carbons with high micropore volume, a traditional alumina (γ-Al2O3) support and its carbon coated form (CCA) were studied for comparison. Coating alumina with carbon increases the selectivity to alcohols, but the AC-supported catalysts show even higher alcohol selectivities and yields, especially at higher temperatures where the conversions over the AC-supported catalysts increase more than those over the γ-Al2O3-based catalysts. Increasing acidity leads to decreased CO conversion yield of alcohols. The two activated-carbon-supported catalysts give the highest yield of ethanol at the highest conversion studied, which seems to be due to increased KCoMoS2 stacking and possibly to the presence of micropores and low amount of mesopores

Study Of (1-Pentyl-1H-Indol-3-Il) (4-Ethylnaphtalene-1-Il)Methanone Adsorption on People Hair

Изучена адсорбция (1-пентил-1Н-индол-3-ил)(4-этилнафталин-1-ил)метанона на измельченных темных и светлых волосах. Определена максимальная предельная адсорбция для обоих типов волос. Построены изотермы адсорбции и проанализированы с использованием модельных уравнений. Установлено, что наиболее точно адсорбция (1-пентил-1Н-индол-3-ил) (4-этилнафталин-1-ил)метанона описывается моделью Фрейндлиха, которая характеризует гетерогенность поверхности волос. Определено общее число электроноакцепторных центров поверхности волос по адсорбции пиридина. Установлена зависимость предельной адсорбции (1-пентил-1Н-индол-3-ил)(4-этилнафталин-1-ил)метанона от кислотности поверхности. Высказано предположение о зависимости адсорбции анализируемого вещества на волосах от количества пигмента меланина, что объясняет превосходство предельной адсорбции на темных волосах по сравнению со светлымиAdsorption of (1-pentyl-1H-indol-3-il)(4-ethylnaphtalene-1-il)methanone on blended black and white hair samples was studied. Absolute adsorption amount was calculated for both hair types. Also adsorption isotherms were constructed and analyzed using different adsorption models. It was estimated that adsorption of (1-pentyl-1H-indol-3-il)(4-ethylnaphtalene-1-il)methanone is best described by Freindlich model which characterizes hair surface heterogeneity. Total amount of electron acceptor centers of hair surface was estimated using pyridine adsorption. Depending absolute adsorption of (1-pentyl-1H-indol-3-il)(4-ethylnaphtalene-1-il)methanone on surface acidity was found. It was suggested that analyte’s adsorption on hair depends on melanin amount. This idea explains that absolute adsorption on black hair is higher than on whit

Features of the Catalytic Cracking of Propane with a Step-Wise Change Pr_xYb_2−xZr₂O₇

In this paper, the features of catalytic cracking of propane with a step-wise change in the composition of the catalyst from Pr2Zr2O7 to Yb2Zr2O7 were considered. For the research, samples of catalysts Pr2Zr2O7, (Pr0.75Yb0.25)2Zr2O7, (Pr0.5Yb0.5)2Zr2O7, (Pr0.25Yb0.75)2Zr2O7 and Yb2Zr2O7 were synthesized and analyzed. Analysis of the results from catalytic experiments showed that for the catalyst (Pr0.25Yb0.75)2Zr2O7, at a temperature of 700 °C, the conversion of propane reaches values of 100%, but for Yb2Zr2O7, this indicator decreases to 84%. The selectivity for ethylene is consistently reduced from 85% to 28% in several catalysts (Pr0.75Yb0.25)2Zr2O7 > Pr2Zr2O7 > (Pr0.5Yb0.5)2Zr2O7 >(Pr0.25Yb0.75)2Zr2O7 > Yb2Zr2O7. An increase in the number of surface adsorption centers leads to a predominant rupture of the C–C bond in the propane molecule with the formation of ethylene. When ytterbium ions are introduced into the catalyst, the amount of ethylene in the reaction products decreases, but the selectivity for propylene increases in the series Pr2Zr2O7 0.75Yb0.25)2Zr2O7 0.5Yb0.5)2Zr2O7 2Zr2O7 0.25Yb0.75)2Zr2O7, which is associated with a decrease in the binding energy of carbon atoms in propane with the catalytic center during adsorption

Influences of Co-Content on the Physico-Chemical and Catalytic Properties of Perovskite GdCo_xFe_1−xO₃ in CO Hydrogenation

The effect of the substitution of cobalt into the GdFeO3 perovskite structure on the selective hydrogenation of CO was investigated. A series of GdCoxFe1−xO3 (x = 0; 0.2; 0.5; 0.8; 1) samples were synthesized by sol-gel technology and characterized by XRD, BET specific area, DSC, TG, EDX and XPS. The experimental data made it possible to reveal a correlation between the state of iron and cobalt atoms, the fractions of surface and lattice oxygen, and catalytic characteristics. It has been found that varying the composition of GdCoxFe1−xO3 complex oxides leads to a change in the oxygen-metal binding energy in Gd-O-Me, the ratio of metals in various oxidation states, and the amount of surface and lattice oxygen, which affects the adsorption and catalytic characteristics of complex oxides

Study Of (1-Pentyl-1H-Indol-3-Il) (4-Ethylnaphtalene-1-Il)Methanone Adsorption on People Hair

Изучена адсорбция (1-пентил-1Н-индол-3-ил)(4-этилнафталин-1-ил)метанона на измельченных темных и светлых волосах. Определена максимальная предельная адсорбция для обоих типов волос. Построены изотермы адсорбции и проанализированы с использованием модельных уравнений. Установлено, что наиболее точно адсорбция (1-пентил-1Н-индол-3-ил) (4-этилнафталин-1-ил)метанона описывается моделью Фрейндлиха, которая характеризует гетерогенность поверхности волос. Определено общее число электроноакцепторных центров поверхности волос по адсорбции пиридина. Установлена зависимость предельной адсорбции (1-пентил-1Н-индол-3-ил)(4-этилнафталин-1-ил)метанона от кислотности поверхности. Высказано предположение о зависимости адсорбции анализируемого вещества на волосах от количества пигмента меланина, что объясняет превосходство предельной адсорбции на темных волосах по сравнению со светлымиAdsorption of (1-pentyl-1H-indol-3-il)(4-ethylnaphtalene-1-il)methanone on blended black and white hair samples was studied. Absolute adsorption amount was calculated for both hair types. Also adsorption isotherms were constructed and analyzed using different adsorption models. It was estimated that adsorption of (1-pentyl-1H-indol-3-il)(4-ethylnaphtalene-1-il)methanone is best described by Freindlich model which characterizes hair surface heterogeneity. Total amount of electron acceptor centers of hair surface was estimated using pyridine adsorption. Depending absolute adsorption of (1-pentyl-1H-indol-3-il)(4-ethylnaphtalene-1-il)methanone on surface acidity was found. It was suggested that analyte’s adsorption on hair depends on melanin amount. This idea explains that absolute adsorption on black hair is higher than on whit

Insights into the Reactivity of Gd_2−xSr_xFe₂O₇ (x = 0 ÷ 0.4) in CO Radical Hydrogenation

The effect of strontium substitution in the structure of the complex oxide Gd2SrFe2O7 on the production of light olefins by CO hydrogenation was investigated. Perovskite-type oxides Gd2−xSr1+xFe2O7 (x = 0; 0.1; 0.2; 0.3; 0.4) were synthesized by sol–gel technology and characterized by XRD, Mössbauer spectroscopy, BET specific area, acidity testing, and SEM. The experimental data revealed a correlation between the state of iron atoms, acidity, and catalytic performance. It was found that with an increase in the content of Sr2+ in the perovskite phase, the basicity of the surface and the oxygen diffusion rate increased. This contributed to the CO dissociative adsorption, formation of active carbon, and its further interaction with atomic hydrogen

Synthesis of Oxygenated Hydrocarbons from Ethanol over Sulfided KCoMo-Based Catalysts: Influence of Novel Fiber- and Powder-Activated Carbon Supports

Ethanol has become a viable feedstock for basic organic synthesis. The catalytic conversion of ethanol provides access to such chemicals as diethyl ether, ethyl acetate, and acetaldehyde. Carbonaceous materials are extensively studied as supports for heterogeneous catalysts due to their chemical and thermal stability, high surface area, and tunable texture. In this paper, ethanol conversion over K10Co3.7Mo12S-catalysts supported on novel activated carbon (AC) materials (i.e., novel powder-AC (DAS and YPK-1), fiber non-woven AC material (AHM), and fabric active sorption (TCA)) was investigated. The catalysts were prepared by the incipient wetness co-impregnation method followed by sulfidation. The catalysts were characterized by employing N2 adsorption–desorption measurements, TEM, SEM/EDX, UV–Vis spectroscopy, and XRF. Catalytic performance was assessed in a fixed-bed down-flow reactor operating at 320 °C, 2.5 MPa, and with continuous ethanol feeding in an He atmosphere. Activity is highly dependent on the support type and catalyst’s textural properties. The activity of the fiber-supported catalysts was found to be greater than the powder-supported catalysts. Ethanol conversion at T = 320 °C, P = 2.5 MPa, and GHSV = 760 L h−1 kgcat−1 increased as follows: (38.7%) KCoMoS2/YPK-1 2/DAS 2/TCA 2/AHM. Catalysts supported by powder-AC enhanced the formation of MoS2-crystallites, whereas the high acidity of fiber-AC seemed to inhibit the formation of MoS2-crystallites. Simultaneously, a high surface area and a microporous catalytic structure enhance the formation of oxygenates from hydrocarbons. The dehydration and dehydrogenation reactions, which led to the creation of ethene and acetaldehyde, were shown to require a highly acidic catalyst, while the synthesis of ethyl acetate and higher alcohols required a less acidic catalyst