Silica gels are the porous materials widely employed in both the industry and housekeeping. Domestic manufacturers produce bead and powder silica gels; however, some application fields of silica gels completely depend on the import. So it is necessary to develop technologies for their production, the introduction of which would allow replacing the imported silica gels. The paper describes methods for improving the properties of bead silica gels and new approaches to the production of powder silica gels and silica gels with the ordered pore structure. It was proposed to use inexpensive feedstock for their preparation, particularly, industrial wastes from the production of alumina – Si-stoff, and the natural material – diatomite. By controlling the parameters of deposition and formation of the silica structure it is possible to obtain silica gels with a wide range of pore structure characteristics, which could be used in various application fields.

Endurance tests of the zeolite-containing cobalt catalyst for the Fischer – Tropsch synthesis were carried out in reactor tubes of the size comparable with those used in industrial reactors. During the tests (3000 h), the catalyst activity decreased by 13 %. Deactivation of the zeolite-containing cobalt catalyst was shown to occur due to agglomeration of cobalt clusters and formation of amorphous carbon on their surface. A method of decreasing the catalyst deactivation rate and two methods of the catalyst regeneration were proposed. The method of redox regeneration of zeolite-containing cobalt catalysts allows restoring 98 % of their initial activity.

Isomerization of heptane and hexane and their mixtures in the presence of Pt/WO₃-ZrO₂ catalysts with the tungsten oxide content of 10–35 wt.% was studied. The best characteristics of isomerization of the С₆–С₇ alkanes mixture were observed on the catalysts with the WO₃ content of 15–20 wt.%. According to ammonia thermodesorption data, the number of acid sites typically increases in this range of tungsten oxide content; according to IR spectroscopy of adsorbed CO, this occurs mostly with an increase in the number of Broensted acid sites.

The solid-phase synthesis of model aluminum-molybdenum (Al-Mo) and aluminum-nickel-molybdenum (Al-Ni-Mo) compositions constituting the catalysts for metathesis of propylene was carried out under mechanical action. The structure of model Al-Mo and Al-Ni-Mo compositions was studied using X-ray diffraction analysis, high-resolution transmission electron microscopy, infrared spectroscopy, and diffuse reflectance electron spectroscopy (UV-vis DRS). The latter method revealed the presence of isolated monomeric and oligomeric molybdate compounds in the model Al-Ni-Mo compositions. Granulated catalysts for metathesis were obtained by molding the model Al-Mo and Al-Ni-Mo compositions with aluminum hydroxide followed by calcination. Most active in the metathesis of propylene was the aluminum-molybdenum catalyst containing 2.6 wt.% Ni, 13.0 wt.% Mo and 32.7 wt.% Al. At the process temperature of 200 °С, pressure 0.1 MPa, and weight space velocity of propylene 1 h^–1, the conversion of propylene on this catalyst reached 33.7 %, which makes the catalyst promising for practical application. Therewith, the weight fraction of ethylene in the reaction products was 17.5 %, and butenes – 71.3 %.

The effect of adsorption of the reaction medium components on selective hydrogenation of acetylene to ethylene under the action of supported palladium catalysts is considered. The role of interstitial solid solutions of carbon and hydrogen in palladium, which are formed upon contact of the catalyst with the reaction medium, in the mass-transfer processes between surface and subsurface layer of the active component is revealed. The ratio of activation barriers for ethylene desorption/adsorption processes, which determines the selectivity of acetylene hydrogenation, can change in dependence on the structure of palladium nanoparticles and its electronic state. Therewith, changes in the electronic state affect the energy of activated desorption of ethylene from palladium particles, and their structural features determine the energy of activated adsorption and the subsequent hydrogenation of ethylene to ethane.

Two samples of TiO₂ /Cr₂O₃ composites were synthesized as spherical grains by stepwise thermal treatment of ion-exchange resins, which were preliminarily saturated with chromium cations Cr³⁺ and dichromate anions Cr2O₇ ^2– and covered with a film-forming solution of titania. The modes of calcination were based on thermal analysis and determined by the type of ion-exchange resin chosen as a template. The obtained composites consist mostly of the α-Cr₂O₃ phase, while the content of the TiO₂ phase does not exceed 4 %. The composites retain the spherical grain shape of the initial ion-exchange resins with the size from 370 to 660 μm. Grains of the sample based on cationite, which adsorbs Cr³⁺ ions, have a pore structure with swells and voids. Grains of the sample based on anionite have fractures and cracks over the entire surface due to nonuniform distribution of adsorbed Cr₂O₇^2– anions in the initial anionite. The composites exhibit the catalytic activity in the complete oxidation of p-xylene. The sample based on cationite is more active. This may be related to a smaller accessible specific surface area of titania in the anionite-based sample due to formation of the Ti³⁺ solid solution in α-Cr₂O₃.

The trend of modelling native enzymes is increasing day by day with the motive of mechanistic elucidation of enzyme-catalyzed reactions and the efficiency of catalysts. Most of the metalloenzymes are capable to activate molecular oxygen due to the presence of metal ions. Among these, copper-based metalloenzyme catechol oxidase has an attractive feature of its oxidizing ability to generate ortho-quinones from catechol. Moreover, the conversion of catechol to ortho-quinones is an important tool for the determination of hormonally active catecholamines such as adrenaline, noradrenaline, and dopa. Nevertheless, the use of native enzymes is highly expensive and the employment of biomimetic models can be the best alternative. This review summarizes some of the widely used modelling methods and their successful applications. Additionally, we also briefly elucidated the structure-activity relationship, kinetic studies of the catalytic oxidation of the substrate, and different external actors influencing the catalytic cycle such as pH, temperature, etc.

An investigation was carried out to study the feasibility of using synthesized acid-bearing carbonaceous catalyst (SO₃H–C and PO₄H₂–C) derived from cassava peel for biodiesel production from waste cooking oil (WCO). The catalyst activity was tested using an autoclave type reactor using three different oil to alcohol ratios (1 : 3, 1 : 5 and 1 : 7) at four different temperatures (50–80 °C) for 4 h. Two types of alcohol (i.e. methanol (CH₃OH) and ethanol C₂H₅OH) were used to understand the efficiency of using alcohol in the process. The study indicates that reaction using high ratio of alcohol (1 : 7) generally produced high yield of the biodiesel compared to other ratios. The yield of the biodiesel also increased with increasing temperature over all the reaction systems. The carbon modified with sulphuric acid catalyst showed the highest yield of ~90 %, which was obtained at 80 °C using a 1 : 7 ratio of WCO : alcohol. It was also observed that reaction with methanol produced better yields compared to ethanol reactions where significant differences were observed across both temperature and ratio. The catalysts were characterized using Fourier Transform Infrared Spectroscopy, X-ray powder diffraction and surface area and pore volume analyses. The catalyst is of interest because it is green, non-toxic and synthesized using cassava peel waste.