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Alkane production from fatty acids and their derivatives can be considered one of the most‐studied processes. Such reactions as hydrogenation, hydrodeoxygenation, decarboxylation, and decarbonylation are the main routes for this process. The reaction pathway depends on the nature of the catalyst, the presence of hydrogen, and the hydrogen source. In this work, a mixture of unsaturated fatty acids (oleic and linoleic acids) was converted to alkanes (mainly heptadecane) in a hydrogen‐free atmosphere by using 2‐propanol as hydrogen donor. Transition metal doped Pd catalysts embedded on a porous organic support (hypercrosslinked polystyrene) were used as catalysts. A Pd‐Cu catalyst showed the highest effectiveness, allowing up to 99.9 mol % selectivity to heptadecane to be obtained. The process proceeds through fatty acid esterification, further hydrogenation of double bonds, and decarboxylation to form n‐heptadecane as main product. [ABSTRACT FROM AUTHOR]

Hydrogenation of aromatic compounds is a widely used catalytic process in modern industry. Selective hydrogenation of benzene (BZ)‐toluene (TL) mixtures is an important industrial process as it allows the purification of BZ for further synthetic purposes. In this work, the hydrogenation of a BZ‐TL mixture (at a molar ratio close to 1) was studied for varying reaction parameters (temperature in the range of 100–180 °C and pressure in the range of 1–7 MPa) using Pt‐, Pd‐, and Ru‐containing nanoparticles stabilized by an amino‐functionalized hyper‐crosslinked aromatic polymer (HAP). Among the synthesized catalytic systems, Ru/HAP containing ruthenium(IV) oxide was shown to be the most active and selective one, allowing 44 % selectivity with respect to cyclohexane at nearly 100 % of BZ conversion. [ABSTRACT FROM AUTHOR]

Here, the development of a new catalyst is reported for the selective furfural (FF) hydrogenation to furfuryl alcohol (FA) based on about 7 nm sized Pd−Cu alloy nanoparticles (NPs) formed in inexpensive, commercially available micro/mesoporous hypercrosslinked polystyrene (HPS). A comparison of the catalytic properties of as‐synthesized and reduced (denoted "r") catalysts as well as Pd−Cu alloy and monometallic palladium NPs showed a considerable enhancement of the catalytic performance of Pd−Cu/HPS‐r compared to other catalysts studied, resulting in about 100 % FF conversion, 95.2 % selectivity for FA and a TOF of 1209 h−1. This was attributed to the enrichment of the NP surface with copper atoms, disrupting the furan ring adsorption, and to the presence of both zerovalent and cationic palladium and copper species, resulting in optimal hydrogen and FF adsorption. These factors along with exceptional stability of the catalyst in ten consecutive catalytic cycles make it highly promising in practical applications. [ABSTRACT FROM AUTHOR]

The solubility of synthesis gas was measured in the temperature range of 100–300 °C and pressure range of 1.0–5.0 MPa in polar (2‐propanol) and nonpolar (n‐dodecane) solvents. Thermodynamic parameters of the absorption, such as the Henry constant, absorption enthalpy, and apparent activation energy of absorption, were calculated on the basis of the obtained results. The phase equilibrium was calculated by using the Soave‐Redlich‐Kwong cubic equation of state, which could be used to predict the optimal process conditions for liquid‐phase Fischer‐Tropsch reactions in different solvents. Solubilities of gases in liquids are needed to interpret rate data in gas‐liquid, gas‐liquid‐liquid, and gas‐liquid‐solid reactions. Hence, CO and H2 solubility under the conditions of liquid‐phase Fischer‐Tropsch synthesis were measured and thermodynamic parameters calculated. The SRK equation of state can be used to predict optimal process conditions for liquid‐phase Fischer‐Tropsch reactions. [ABSTRACT FROM AUTHOR]

Deposition of catalytically active metal‐containing compounds on solid porous supports by using superheated (subcritical) water is a promising way to produce materials with unique physicochemical and catalytic properties. The hydrothermal method has been found to give catalysts with high surface area, fine distribution of the active phase, and high catalytic activity. In the current work, the catalytic activities of 10 % Ni and 10 % Co deposited on hyper‐cross‐linked polystyrene (HPS) by the hydrothermal method in the supercritical deoxygenation of fatty acids were compared. 10 % Ni/HPS was found to be the most active catalyst in the deoxygenation of stearic acid in supercritical n‐hexane. Supported metal catalysts play an important role in chemical technology, and hydrothermal synthesis of catalysts has recently attracted much attention. Cobalt and nickel nanoparticles were deposited on a hyper‐cross‐linked polystyrene matrix by a hydrothermal method, and the catalytic activity of the resulting catalysts was evaluated in the deoxygenation of fatty acids in supercritical n‐hexane. [ABSTRACT FROM AUTHOR]

Abstract: Here, we report on the development of novel Cr‐containing magnetic oxide nanoparticles (NPs) as catalysts for a syngas‐to‐methanol reaction which constitutes a sustainable route to obtain value‐added chemicals. These NPs have been synthesized in a one‐pot reaction by thermal decomposition of Cr acetylacetonate and doping metal acetylacetonates (if used) in the reaction solution of preformed magnetite NPs stabilized by polyphenylquinoxaline. For all the samples, the NP surface is enriched with Cr. At the same time, the Cr species are finely dispersed in the magnetite phase. This exposes Cr catalytic species to reacting molecules and creates an intimate contact between Cr3+ and Fe3O4. As a result, the methanol productivity rate for the Cr‐containing magnetic oxide prepared with 0.5 mmol of the Cr precursor is approximately three orders of magnitude higher than that for the conventional Cu/ZnO/Al2O3 catalyst. Additional doping of this Cr‐containing magnetic oxide with small amounts of Ni or La leads to even higher catalytic activity (by 40–49%). [ABSTRACT FROM AUTHOR]