The development of effective bifunctional catalysts demonstrating high performance in both photocatalytic hydrogen evolution and selective hydrogenation of unsaturated compounds is of great interest for photocatalytic transfer hydrogenation. In this work, TiO₂ and Pd@TiO₂ catalysts were studied in two separate processes: photocatalytic H₂ evolution and conventional hydrogenation reactions. Photocatalytic properties of titanium dioxide synthesized by a simple precipitation method were compared with those of commercial ones. Commercial anatase with a lower agglomeration degree showed better activity in H₂ evolution. Further modification of the commercial anatase with Pd resulted in increasing its activity, achieving an H₂ evolution rate of 760 μmol/h g_cat. The Pd catalysts supported on different TiO₂ samples were tested in hydrogenation of acetylenic compounds. The activity of the Pd@TiO₂ catalysts was found to be dependent on the photocatalytic properties of TiO₂ supports. XPS studies of Pd catalysts indicated that commercial anatase with better photocatalytic properties provided easier reduction of Pd²⁺ to active Pd⁰ particles. The Pd catalyst supported on commercial anatase demonstrated the highest activity in the hydrogenation process. The W_C≡C rate achieved 2.6 × 10⁻⁶, 9.0 × 10⁻⁶ and 35.7 × 10⁻⁶ mol/s for hydrogenation of 2-hexyne-1-ol, 5-hexyne-1-ol and 2-hexyne, respectively. The selectivity of the catalyst to target olefinic compounds was 94–96%. In addition, the hydrogenation rate was found to be significantly affected by reaction conditions such as hydrogen concentration and solvent composition. The W_C≡C rate decreased linearly with decreasing hydrogen concentration in a H₂:He gas mixture (30–100 vol%). Performing the reaction in 0.10 M NaOH ethanolic solution resulted in increasing the W_C≡C rate and selectivity of the process. The Pd catalyst was reused in an alkali medium (NaOH in ethanol) for 35 runs without significant degradation in its catalytic activity. Thus, the results obtained in this work can be useful in photocatalytic transfer hydrogenation.

This work aims to study the catalytic properties of Fe, Cr, and Cu catalysts deposited on chitosan–silica (SBA-15) composites in liquid phase oxidation of cyclohexane (CH) with H₂O₂ and photocatalytic hydrogen evolution reaction. The catalysts were obtained by consecutive adsorption of chitosan (CS) and metal ions (Fe³⁺, Cr³⁺, Cu²⁺) on SBA-15 at ambient conditions. Characterization of the catalysts by XRD, IR spectroscopy, XPS, TEM, SEM, etc., showed the CS and metal ion adsorption on the solid support. Modification with CS provided better immobilization of the metal ions on SBA-15. The synthesized catalysts demonstrated different performance in liquid phase oxidation of cyclohexane with H₂O₂ under mild conditions at 40 °C and atmospheric pressure. Cyclohexane conversion on Fe–CS/SBA-15 (18.5%) and Cr–CS/SBA-15 (21.6%) was higher than on Cu–CS/SBA-15 (9.3%). The influence of different conditions of the reaction such as time, temperature, catalyst dosage, substrate and oxidant ratio on cyclohexane conversion in the presence of the most efficient Cr–CS/SBA-15 catalyst was also studied. The optimal reaction conditions were found to be the following: duration of reaction—4 h, temperature of reaction—50 °C, m_cat—0.03 g, a substrate/H₂O₂ ratio of 1:3. In addition, Cr–CS/SBA-15 and Fe–CS/SBA-15 catalysts were studied in a photocatalytic H₂ evolution reaction. The Fe-containing catalyst demonstrated superior efficiency in photocatalytic H₂ evolution. The total volume of hydrogen produced within 3 h was 103 mL/g. Thus, this study demonstrates that chitosan possesses promising potential in the design of the supported catalysts for cyclohexane oxidation and photocatalytic hydrogen evolution reactions.

This study investigates the influence of pectin and copper incorporation on the catalytic properties of Pd/ZnO catalysts in the liquid-phase hydrogenation of 2-hexyn-1-ol and photocatalytic hydrogen evolution. A series of monometallic Pd/ZnO catalysts with varying pectin contents (0–8.1 wt%) and bimetallic PdCu-Pec/ZnO catalysts with different Pd to Cu mass ratios (3:1, 1:1, 1:3) were synthesized via sequential adsorption of the polymer and metal ions onto ZnO. The catalysts were characterized using TGA, EDX, IR spectroscopy, XRD, TEM, UV–Vis DRS, and XPS. Characterization confirmed successful modification and changes in surface properties. Pectin modification improved the distribution of Pd nanoparticles on the surface of ZnO, resulting in the enhanced catalytic performance of Pd-Pec/ZnO in both hydrogenation and hydrogen evolution reactions compared to unmodified Pd/ZnO. In contrast, copper addition led to a deterioration of catalytic properties in both processes, likely due to the inhibited reduction of Pd caused by Pd–Cu interactions. Among the catalysts studied, Pd-Pec/ZnO with low pectin content (1.8 wt%) exhibited the highest activity in both reactions. The hydrogenation of 2-hexyn-1-ol to cis-2-hexen-1-ol proceeded with high selectivity (96%) at a rate (W_C≡C) of 3.3 × 10⁻⁶ mol/s, and the catalyst retained its activity over 30 consecutive runs. In the photocatalytic hydrogen evolution reaction, the rate reached 1.11 mmol/(h·g_cat) and the catalyst maintained ~94% of its initial activity after three consecutive runs. These findings demonstrate the potential of biopolymer-modified ZnO composites for the design of multifunctional catalysts combining hydrogenation and photocatalytic activity.

The results of the oxidative desulfurization process (combination of straight-run gasoline fraction and gas condensate oxidation with subsequent rectification) are presented. It is shown for the first time that it is possible to obtain a gasoline fraction with ultra-low sulfur content by oxidation and rectification of gas condensate. Optimum conditions have been selected for the process of sulfur compounds oxidation and subsequent rectification of gas condensate.

Background: Nowadays, there are few studies focused on the extraction of targeted products from bituminous rocks. Published research on the on the use of ultrasound for bitumen extraction refers to unconventional technologies. A distinctive feature of the bituminous rocks under study is their exposure at the surface, where they are situated in open areas. Due to various technogenic factors and prolonged atmospheric, light fractions are lost, while the heavier components undergo oxidation. These processes lead to the formation of heavy oils and hard bitumens with complex composition. Aim: To study the effect of ultrasonic technology on the bitumen extraction of from bituminous rocks and to determine the physical and chemical properties of the product obtained. Materials and methods: Thу ultrasonic method has many benefits, in particular energy and water savings, high productivity within a short period of time, and possibility of organizing a mobile unit installation at the production site. The main process parameters includes the determination of the required frequency and power depending on the object of ultrasound technology research. The results of the work have demonstrated that ultrasonic cavitation of bituminous rocks in an alkaline medium increases the degree of bitumen extraction. Results: The physical and chemical properties of bitumen obtained as a result of studying the effect of ultrasonic technology on bitumen extraction from oil-bituminous rocks were determined. Conclusion: The study identified the optimal process parameters based on the specific research object. When selecting the ultrasonic power it was found that clay compounds of bituminous rocks have a direct effect on the extraction of natural bitumen. It was demonstrated that ultrasound technology is a promising and industrially applicable technology for extracting bitumen from the bituminous rocks of the Munaily Mola field.