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This article presents the results of a study of cleaning the water surface from contamination with petroleum products. Kulantaussky vermiculite, the birthplace of the Turkestan region, was studied as a sorbent. Studies have shown that the modified vermiculite is able to retain the sorbed oil up to 2 days after the expiration of the main sorption time (4 hours). It is established that the oil capacity depends on the thickness of the oil film, the sorption time and the amount of the sorbent taken.

Research is conducted on the development of paper packaging materials with antibacterial properties using titanium dioxide nanoparticles. Titanium dioxide nanoparticles are synthesized by the hydrolysis of titanium tetrachloride in an alkaline medium, adjusting the pH value with an aqueous solution of ammonia at a temperature of 30 to 60°C. The influence of reaction conditions on the synthesis of titanium dioxide nanoparticles and the pH of the medium are studied and the optimal synthesis conditions are found. The processing parameters of paper packaging materials with aqueous solutions of titanium dioxide nanoparticles, which give them antimicrobial properties, are determined. Using electron-scanning microscopy and energy dispersive microanalysis, it is shown that untreated packaging paper contains 64.69% of C and 35.31% of O; after modification with a solution of titanium dioxide nanoparticles, titanium dioxide particles, which are distributed quite unevenly depending on the initial concentration of titanium dioxide nanoparticles, form on 16.46–21.14% of the surface of the treated paper. The packaging materials modified by the proposed composition show strong resistance to the action of microorganisms. The use of the developed antimicrobial food packaging reduces losses and preserves the quality and safety of food products during transportation, storage, and sales.

The depletion of ores, a rise in the cost of their extraction, enrichment and processing led in the last 10‒15 years to a sharp rise in prices for tungsten products. Therefore, the processing began to involve technogenic waste ‒ dumps of enrichment factories and metallurgical industries, which previously did not represent the commercial interest on this case, we present the information on the results of the thermodynamic modeling of tungsten and bismuth chloride distillation in the processing of industrial waste using NaCl as a chlorinating agent. To calculate thermodynamic models for the associated extraction of tungsten and bismuth from industrial wastes, the ASTRA-4 software complex was used which created on basis of the maximum entropy of all possible reactions occurring during the retrieval of refractory metals from waste. Thus, the calculations carried out and experimental studies of the main provisions of thermodynamic calculation have shown the possibility of using NaCl salts for bismuth chlorination. At the same time, the maximum degree of sublimation of bismuth not be lower than 98% and can be achieved even at a temperature of 1200 K and a pressure of 0.01–0.1 MPa. At the same time, NaCl is not an effective chlorinating agent for retrieving of tungsten during high-temperature processing of industrial wastes.

General principles of effect of the nature of metal-catalyst, carrier, solvent, method of preparation and temperature of catalyst reduction and other parameters (PH2, T, etc) on the process of hydrogenolysis of “binor-S” into pentacyclotetradecane have been studied and stated. On the basis of the results obtained a new effective and economical method of diamantane isomer synthesis has been elaborated. The presence of supported platinum catalyst (10-15% Pt/C) allows to proceed the reaction under mild conditions (0.1-10 MPa, 60-80 °C and in non-aggressive medium (water) with a quantitative yield of the product. It was stated with the help of a complex of physico-chemical methods of investigation (RPES, IR-spectroscopy, NMR, 13C, PMR, etc) that the methods of preparation and the temperature range of reduction of supported platinum catalysts contributing to the formation of highly dispersed metal particles (2.5-5.0 mm) and their uniform distribution on the carrier surface increase the activity and selectivity of platinum in the reaction of hydrogenolysis of “binor-S” into pentacyclotetradecane. It was shown that the more is the dispersity of metal and the value of the carrier surface, the higher is the activity and selectivity of supported platinum catalysts due to the peculiarity of electronic structure of small particles as well as the influence of the carrier on stabilization of the metal surface structure, i.e. the process of hydrogenolysis of “binor-S” belongs to the type of structure-sensitive reactions.