The influence of temperature of ageing of the initial silicoaluminophosphate gel on crystallization of the molecular sieve SAPO-11 was studied. It was established that with pseudoboehmite used as the source of aluminum, a gel containing di-n-propylamine phosphate, non-dissolved pseudoboehmite and amorphous silicoaluminophosphate was formed. Elevation of the gel ageing temperature from 25 to 90 °C was shown to result in an increase in the proportion of the amorphous phase in the gel. Crystallization of the silicoalumophosphate gel at 90 °C allowed SAPO-11 to be crystallized at high phase purity and close to 98 % crystallinity. A high activity and selectivity (86 %) of SAPO-11 to linear dimmers was observed during dimerization of α-methylstirene.

The effect of the synthesis conditions – features and content of an alkali used for hydration of the gibbsite thermal activation product, and the content of nitric acid (acidity modulus) used to obtain the extrusion paste – on the properties of alumina desiccants was studied. The synthesized desiccant outperforms foreign and Russian analogs in dynamic capacity (above 10.0 g/100 g) at close values of specific surface area (ca. 300 m²/g) and static capacity (20–22 g/100 g). The desiccant has a high strength (above 8.0 MPa). Its application can increase the performance of existing adsorbers and decrease the cost of sorbent regeneration, which is certainly of practical interest.

The effect of gas recirculation on the production of long-chain C₃₅₊  hydrocarbons over supported Co-Al₂O₃/SiO₂ catalyst at a pressure of 6.0 MPa, temperature 225 °C and gas hourly space velocity 1000 h^–1 was studied. It was shown that the circulation mode provides isothermicity of the catalyst bed and increases the selectivity to C₃₅₊ hydrocarbons and their output. The study revealed that the catalyst deactivation rate decreases by a factor of 8 when the circulation ratio is raised from 2.2 to 6; therewith, the content of unsaturated hydrocarbons in the synthesis products increases twofold.

In the context of utilization of carbon dioxide emissions, a study of the CO₂ conversion to methanol and dimethyl ether (DME) under flowcirculation conditions, when a part of converted gas returns to the reactor, was carried out. Experimental data on the synthesis of methanol (commercial catalyst Megamax 507) and direct synthesis of DME (Megamax 507/commercial zeolite ZVM, weight ratio 1/1) are reported. In the methanol synthesis from syngas, vol.%: H2 – 76.6, CO₂ – 19.8, N2 – 3.6 performed at 240–260 °C and pressure 5.3 MPa, a high conversion of CO₂ was reached: 84–99.6% at a low selectivity of the side reaction (CO synthesis, not higher than 4.7 %). The maximum specific yield of methanol at 260 °C was 1.24 kg(kgcat·h)^–1. Special-purpose experiments demonstrated that the methanol synthesis is accompanied by a small heating (up to 10 °C) at the catalyst bed inlet, which testifies to polytropicity of the reactor. In the synthesis of DME, the DME yield referred to bifunctional catalyst was within 0.16–0.33 kg(kgcat·h)^–1 depending on the conditions. Therewith, the conversion of methanol to DME was not lower than 42 %, the conversion of CO₂ was within 79–96 %, and the DME synthesis proceeded under nearly isothermal conditions.

In search for the improved catalytic efficacy, considerable attention has been focused on mixed metal oxides in the last decade. The present study reports catalytic activity of mesoporous mixed metal oxide, Zr₆Nb₂O₁₇ for the first time. In this study, the mesoporous Zr₆Nb₂O₁₇ has been synthesized through a soft template based wet chemical approach. The mesoporous Zr₆Nb₂O₁₇ is realized after the removal of surfactant through calcination at 500 °C, and preserves its mesoporosity after crystallization by heat-treatment at 550 °C. The synthesized oxide exhibits surface area as high as 221 m²/g and pore size of 3.3 nm with narrow pore size distribution. The synthesized mesoporous Zr₆Nb₂O₁₇ shows significant catalytic activity for the bromination of phenol red. Careful structural characterizations and catalytic activity studies of the mesoporous Zr₆Nb₂O₁₇ are documented in this report.

The two-step conversion of industrial liquefied hydrocarbon gases (LHG) on NIAP-07-01 (NKM-1) and NIAP-03-01 catalysts for the production of hydrogen-containing gases was investigated. The experiments were carried out in flow reactors with a fixed catalyst bed at a pressure of 0.1 MPa under the following conditions: temperature 350–450 °C, gas hourly space velocity (GHSV) 1000–3000 h^–1, steam-gas ratio 4 : 1–8 : 1 (pre-reforming); and temperature 700 °C, GHSV 2000 h^–1, air-gas ratio 1.2 : 1 (steam-air reforming). Under the studied conditions, the concentrations of components of the converted gas correspond to the equilibrium values calculated within the Peng-Robinson model. The conversion of methane homologs in the pre-reforming step was found to be virtually 100 %; therewith, the methane concentration reached 32–54 %, and that of hydrogen, 24–47 %. To prevent the formation of elemental carbon (carbonization), pre-reforming of hydrocarbon gases with a high methane equivalent should be performed at H₂O : C > 2. In the two-step reforming, the yield of hydrogen-containing gas reaches 15.6 m3 from 1 m³ of the initial LHG with the hydrogen content 41.81 %, and the total content of CO and H₂ exceeds 52 %.

The study is devoted to multicriteria optimization of the operation of the reactor unit intended for reforming of oil fractions. The optimization is based on the earlier developed mathematical model, which can take into account changes in the temperature and molar consumption of the reaction mixture during chemical transformations, the composition of the feedstock being processed, and the circulation quality and ratio of the hydrogen-containing gas. The following criteria are used in such optimization: octane number, yield of the target product (reformate), content of the sum of aromatic hydrocarbons, and content of benzene. The optimization was implemented using Pareto approximation with the genetic algorithm. Temperatures at the reactor inlets served as the control parameters. As a result of optimization, the sum content of aromatic hydrocarbons decreases from 56 to 45 wt.%, and the octane number measured by the research method (RON) decreases from 92.7 to 90.7 points. The three-criteria optimization is also considered; it provides a decrease in the benzene content from 4 to 3.08 wt.% with a decrease in RON from 92.7 to 91.8 points. In both cases, the decrease in the octane number is admissible, taking into account the fulfilled requirements to the limiting content of benzene and aromatic hydrocarbons in the reformate.

In industrial chemistry, there is a growing demand for the precursors obtained by bioengineering methods; particularly, bioethanol can be used for the production of ethylene. In this study, Miscanthus sacchariflorus was used for the first time as a feedstock for the production of bioethanol. The step of miscanthus chemical treatment with a 4 wt.% solution of nitric acid was successfully scaled up under the conditions of pilot-plant production; the product of nitric acid treatment (PNAT) was obtained with the yield of 37.4 % and the content of hydrolyzed components equal to 96.0 %. It was shown that the chemical pretreatment of miscanthus with nitric acid, irrespective of its breed, makes it possible to obtain substrates with close chemical compositions. The goal of the study was to perform the primary scale-up of the joint saccharification-fermentation of miscanthus-derived PNAT in an 11 L fermenter (at a scaling factor 1 : 8) with increasing the PNAT concentration from 60.0 to 90.0 g/L. Saccharification was carried out using the commercially available enzymatic preparations Cellolux-A and Bruzyme BGX, and fermentation – using the VKPM yeast strain Saccharomyces сerevisiae Y-1693. It was found that as the substrate concentration is raised from 60.0 to 90.0 g/L, the concentration of bioethanol increases by 9.5 g/L; the substrate concentration of 90.0 g/L was recommended for use in the process scale-up for the pilot-plant production. A scheme of bioethanol production yielding 202 L of bioethanol from ton of miscanthus was proposed.

Lignocellulose is a global inexhaustible resource for obtaining various products of biotechnological synthesis. The enhanced efficiency of glucose extraction from lignocellulose will increase the yield of such products, thus decreasing their cost. The goal of the study was to optimize the composition of multienzyme cocktail (MEC) of commercial enzymatic preparations (EP) Cellolux-A, Ultraflo Core and Bruzyme BGX for efficient enzymatic hydrolysis of the substrate – oat husk treated with 4 wt.% nitric acid under the pilot-plant conditions. Mathematical processing of experimental data obtained by implementation of the simplex-centroid design of experiments revealed the optimal EP ratio equal to 1/4 : 3/4 : 0 (Cellolux-A – 18 mg/g substrate, Ultraflo Core – 55 mg/g substrate). The optimized composition of MEC allows increasing the reducing substances yield by a factor of 1.95. The equation of experimental statistical model was used to investigate the hydrolysis kinetics at different concentrations of MEC. It was shown that a threefold increase in the MEC concentration increases the reducing substances yield versus the substrate weight and the glucose yield versus the cellulose weight in the substrate by 13 %. The hydrolysate obtained using the optimized MEC served as a nutrient medium for biosynthesis of a valuable bioengineering product – bacterial nanocellulose, the yield of which constituted 6.1 % of the hydrolysate glucose.