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Results of systematic investigation of the physicochemical features of the formation and isomerizing activity of catalysts based on zirconium dioxide modified with sulpahte and tungstate anions and various trivalent cations, depening on the composition and preparation conditions, are presented.

Methods of synthesis of betulin diacetate and dipropionate from birch bark are proposed. The methods are based on combined extraction of betulin from birch bark and its acylation with acetic and propionic acids. The structure of the resulting betulin derivatives was confirmed by means of chromatography - mass spectrometry, FTIR and NMR spectroscopy.

Problems connected with processing of underground polycomponent brines of the Krasnoyarsk Territory are to a large extent due to the remoteness of deposits and the absence of developed infrastructure. The version involving direct extraction recovery of valuable elements in the form of salts is considered. It is shown that the highest salt concentrating degree may be achieved for extraction of calcium bromide and lithium chloride (by a factor of 20 and 40, respectively). A scheme of extraction recovery of calcium bromide with a mixture of tributylphosphate and molecular iodine is proposed. Problems of lithium chloride extraction are considered. For the example of extraction of lithium tetraphenylborate, LiFeCl₄ and Li(ClI₂) in the systems with tributylphosphate, it is established that the growth of steric hindrance for the formation of extracted complexes promotes the recovery of lithium from calcium chloride brines.

Technological problems of processing rare metal ores of the Chuktukon deposit (Krasnoyarsk Territory) are considered. Oxide ferrimanganese ores contain 3-7 % earth oxides in the form of phosphates (monazite, florencite) and 0.5-1 % niobium oxide (chalcolamprite) and are practically undressable. The possibility of their direct chemical processing was studied. A scheme including autoclave nitric acid leaching and extraction of rare earth elements, reductive treatment of leaching tailings and isolation of niobium concentrate into the non-magnetic fraction was proposed. According to this scheme, nitrate solutions are subjected to thermal decomposition in order to recover nitric acid. The pyrometallurgical process of ore reduction leading to cast iron and rare metal products was analyzed. Process realization requires solution of complicated technological problems in obtaining high-quality products.

For the synthesis of palladium acetate [Pd(CH₃COO)₂]₃ as example, the features of the behaviour of pallaium nitrate solution as a precursor for the technology of industrial synthesis of palladium salts without chlorine-containing reagents aer studied. It is discovered that the oxygenated compounds of nitrogen that are present in the solution affect branching of the syntheis trajectory. It is shown that the formation of the final products proceeds through a series of intermediate stages at which new and already known chemical compounds were isolated: [Pd₃(CH₃COO)₆], [Pd(NO)₂O], [Pd(NO)NO₂], [Pd₂(CH₃COO)₂(NO)₂]₄, [Pd₆O₂(CH₃COO)₃(NO₂)_{6 - x}(NO)_x](H₃O)(H₂O)₅ (x = 0-3), [Pd₃(CH₃COO)₅NO₂], катена-[Pd(CH₃COO)₂]_n, catena-[Pd(HCOO)₂]_n, catena-[Pd(NO)₂Cl₂]_n, catena-[Pd(NO)X]_n (X = Cl or Br). Isolation and investigation of intermediate products allowed us to propose a scheme of the transition of the nitrate coordination surroundings of palladium into the acetate one. Side processes realized in the system are initiated, as a rule, by nitrosation reactions. On the basis of the data obtained, a set of industrial methods of obtaiing palladium acetate was developed.

Extraction processes developed and introduced by the authors at the Norilsk Mining and Smelting Plant (at present ZF OAO GMK "Norilsky Nikel") during the years 1979 to 2009 are considered.

Results of the investigation of reagent regimes and technological operations of gold recovery into concentrates from the ores of parent deposits and technogenic gold-containing raw material of the Krasnoyarsk Territory. Investigations were carried out at the Institute of Chemsitry and Chemcial Technology SB RAS and at the Institute of Nonferrous Metals and Materials Science of the Siberian Federal University during the recent decade. Dependencies of ore concentrability on the mineral and granulometric composition were established. Ways to impromenet of the quality of gold-containing concentrates are shown, new floatation agents are recommended along with new operations of fine gold concentrating, including afterconcentration of old dumps and tailings. Technological operations for the treatment of different hypergene deposits based on stagial combination of various mining and concentrating technologies were rpopsoed for the first time.

Results on the methods of obtaining and the properties of ultrahigh-molecular polyethylene (UHMP) are presented. Items made of this material survive rigid performance conditions, unlike for usual grades of the polymer. It was demonstrated that modification of UHMP by introducing ultrafine particles of inorganic materials promotes enhancement of the performance characteristics of the items made of UHMP. Results of investigations in the area of the development of technologies for obtaining items made of the composite materials based on modified UHMP. New rubber-polymer materials based no modified UHMP, butadiene-nitrile, cis-isoprene and divinyl caoutchouc were obtained. Due to extremely low abradability and increased performance resources of the items made of the developed materials under extremal performance conditions, the materials may win broad range of applications in various areas of technology.

Features of the treatment of non-yielding materials in open and closed systems are considered. The possibility to increase the efficiency of decomposition of difficultly processable ores and concentrates of precious metals in open systems with the use of low-temperature alkaline fusion and acidic oxidative treatment in closed systems - in autoclaves using the microwave radiation is demonstrated.

Possibility of the polymerization of α-angelicalactone (5-methylfuran-2(3H)-one) via two major routes - by opening the olefin bond and/or opening of the lactone bond - is demonstrated. Polyesters of α-angelicalactone were obtained on basic catalysts. Liquid and solid polymers with the molecular masses (MM) 840 to 100 000 were synthesized. It was shown by means of NMR that the fraction of polyester intermonomer bonds in them is 60-68 %. Copolymers of α-angelicalactone with styrele additives were obtained; their ММ was about 200 000-500 000. It was shown that the obtained polymers are subject to biodegradation by different microorganisms within a time interval from a month to half a year.