Rice husk is a large-tonnage waste left from rice production. It is not subject to humification and therefore becomes a serious environmental pollutant. Due to the presence of two essential elements—carbon and silicon—in its composition, rice husk is a promising organo-mineral raw material. The known methods for processing of rice husk are associated with the formation of even more aggressive waste. The creation of a waste-free technology for processing this plant material requires a detailed study. Rice husk of yzylorda oblast was studied using IR, SEM, TA, TPD-MS, EPR, and TEM methods. It was determined that under a temperature up to 500 °C, the ligno-carbohydrate component of rice husk decomposes almost completely. Three main peaks are recorded during the decomposition: hemicellulose at 200 °C, cellulose at 265 °C, and lignin at 350–360 °C. This process is endothermic. However, above of 300 °C the exothermic reactions associated with the formation of new substances and condensation processes in the solid residue begin to prevail. This explains the increase in the concentration of paramagnetic centers (PMCs) in products of rice husk carbonization in the range of up to 450 °C. Further increase in temperature leads to a decrease in the number of PMCs as a result of carbon graphite-like structures formation. The silicon–carbon product of rice husk carbonization (nanocomposite) is formed by interconnected nanoscale particles of carbon and silicon dioxide, the modification of which depends on the temperature of carbonization. The obtained data allow management of the rice husk utilization process while manufacturing products in demand based on ecofriendly technologies.

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Scientific bases of self-propagating high-temperature synthesis of refractory materials, recipes, and methods for their creation from local raw material are developed. Thermochemical and kinetic parameters for solid-phase synthesis of systems based on chamotte, chromite, magnesium, and aluminum sulphate, and also phase composition, thermodynamic and physicomechanical properties of the products obtained are determined.Self-propagating high-temperature synthesis (SHS) is one of the promising resource saving and highly productive methods for preparing refractory inorganic compounds, hard, alloys, and refractory materials. SHS is used for preparation of refractory inorganic sheets, objects, coatings with use of mixtures of metal oxides with metal reducing agents and nonmetals as raw materials. This method has been used to prepare a broad range of cast carbides and other hard alloys based on them, a number of borides, and also some silicides and intermetallics. All of these materials have been prepared mainly from chemically pure reagents, whose use increases the cost of synthesized materials. In view of this there is a requirement for carrying out research aimed at use in this process of available raw materials. This work has been carried out in the Institute of Physical Chemistry, Russian Academy of sciences (Chrnogolovka, Moscow region, Russia) under the leadership of A. G. Merzhanov, M. D. Nersesyan, and I. V. Borovinska, Results of studying the SHS mechanism for refractories has been aired in the work of V. I. Yukhvid, E. A. Levashov, and V. N. Shkiro, and others. In Kazakhstan since 1984 in the Chemical Kinetics and Combustion faculty of the S. M. Kirov KazGU under the leadership of G. I. Ksandopulo and M. B. Ismailovthe mechanism of combustion of sodium-thermal systems has been studied leading later to work for an SHS-refractory. However, until recently there has not been a systematic study and practical analysis of creation of highly effective refractory materials for metallurgical units by the SHS method.Studies, carried in RGP National Center for Complex Processing of Mineral Raw Material of the Kazakhstan Republic (RK), and also tests performed in OAO Korporatsiya Kazakhmys, OAO, Kaztsink, OAO Mittal Stil Temirtau, AO TsentralAziyaTsement, AO Transnational Company Kazkhrom, i.e. Aksysk Ferroalloy Plant, TOO Ferrum-Vtor, OOO Staro-Oskol Metallurgical Combine (Staryi Oskol, Russia), and other companies, have made it possible for the first time to develop a theoretical basis for self-propagating high-temperature synthesis of refractory materials and technology for their manufacture from local raw materials, and also to demonstrate the efficiency of their use in metallurgy.Over a number of years more than 35 new forms of refractory materials have been developed (magnesia, chromite-periclase, forsterite, dolomite, dinas) [1 -3], and they have been tested industrially and introduced into ferrous and nonferrous metallurgy enterprises of the Kazakhstan Republic. MAGNESIA REFRACTORIESExamples are provided in Tables ...

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