To the 70-th anniversary of the chair of “Chemistry and technology of rare and scattered elements” of Lomonosov mitkht

• Timofeev V.S. Foreword
• Drobot D.V. From the history of the chair of “Chemistry and technology of rare and scattered elements” of Lomonosov MITKhT
• Izotov A.D. The base chair of “Chemistry and technology of inorganic substances and materials” under the Kurnakov Institute of General Inorganic Chemistry of Russian Academy of Science
• Krokhin V.A. The base chair of “Progressive technologies of raw rare metals processing” under the GNTs GIREDMET
• Chub A.V. The base chair of “Technology of deep reprocessing of complex rare-element raw materials” under OAO “Solikamsk manganese plant”
• Tomashpolsky Yu.Ya. The base chair of “Synthesis and characterization of inorganic films” under GNTs Karpov NIFKhI

Chub A.V., Dobrynin A.I., Fomin A.V., Drobot D.V., Tsurika A.A. Chlorination of ferroniobium
A study has been made of the chlorination processes of ferroniobium containing (in %) 45-47 Nb, 4-7 Ta, 28-30 Fe, 3-5 Mn, 3-5 Sn, 3-4 Si, 3-12 Al, up to 2 Ti, Zr<0,3, Pb£ 0,2 and W£ 0,5 by gaseous chlorine in salt chloride melts (spent electrolyte of magnesium production) and lump ferroniobium in the absence of melt. The thermodynamic data of the main reactions were calculated. In chlorination of lump ferroniobium for lack of chlorine, the separation of the main iron mass from niobium and tantalum is shown to be possible in the chlorination stage yet.

Bukin V.I., Smirnova A.G., Reznik A.M. Extraction of vanadium (V) by nitrogen-bearing oligomers
The methods to extract vanadium and manganese out of waste processing solutions of a number of productions using available domestic oligomeric extractants of phenolic type have been developed and tested. The extraction of vanadium into an extract is 99,9 % and this of manganese is 95,3 %. Extracting conditions for vanadium (V) and manganese (II) (pH, salt background, composition of extracting agent, etc.), the chemism of their extraction, and the compositions of extractable complexes were determined. The process flowsheet for extraction and separation of vanadium (V) and manganese (II) has been developed and tested.

Shcheglov P.A., Drobot D.V. The P-T-x phase diagram of rhenium-oxygen system
Heterogeneous phase equilibria in the rhenium-oxygen system have been studied. Samples of the system obtained by mixing of Re₂O₇ and ReO₂ oxides were studied by means of DTA, XRDA, and tensimetry (static method). No phases have been found except Re₂O₇, ReO₃, and ReO₂ in the rhenium-oxygen system. A variant of P-T and T-x projections of the phase diagram of the rhenium-oxygen system is proposed.

Nikishina E.E., Lebedeva E.N., Drobot D.V., Korovin S.S. Low hydrated niobium and tantalum hydroxides as precursors for synthesis of complex oxides
DTA, DTG and XRDA were used to study thermal properties of low hydrated niobium and tantalum hydroxides obtained by heterophase interaction of niobium and tantalum pentachlorides and ammonia solution. The dependence of sorption properties of low hydrated niobium and tantalum hydroxides on the concentration of acetic magnesium solutions (C = 0,256-0,663 mole/l), temperature (T = 0,20 ° C), and thermal pretreatment (T = 420 ° C) has been studied. Based on the sorption properties, the application of low hydrated niobium and tantalum hydroxides is shown to be promising in synthesis of complex niobates and tantalates.

Belov S.F., Avaeva T.I., Seredina G.D. Behaviors of chemical reactions of the same type in fluoride-oxide melts
Results of the study of chemical reactions which run in fluoride-oxide melts have been generalized. Using the methods of comparative calculation of physical-chemical properties of the substances, the behaviors of the reactions were found, i.e., linear dependences between equilibrium constant logarithms of the reactions of the same type. The obtained dependences make it possible to determine the equilibrium constants of experimentally unstudied reactions.

Zimina G.V., Slivko T.A., Smirnova I.N., Bobylev A.P., Golubina L.V., Komissarova L.N. Physical-chemical fundamental of complex apatite concentrate processing
A scientifically reasoned process flowsheet of integrated apatite processing has been developed, at the basis of which the decomposition of apatite concentrate by phosphoric acid under hydrothermal conditions at 150 ° C and 200 ° C (10-12 atm) is taken. An original unit of the process flowsheet, which comprises the decomposition of apatite with its simultaneous defluorination and production of RE or RE-Sr concentrates. The physical-chemical fundamental of the processes in decomposing and defluorinating apatite and separation of RE and RE-Sr concentrates have been studied. This makes it possible to use the scientific approach to the control of all the process stages. The proposed method of apatite processing provides for 100 % removal of fluorine and its utilization, extraction of 90 % RE and 75 % Sr, and production of pollution-free precipitates.

Zimina G.V., Novoselov A.V., Filaretov A.A., Payachkovskaya A., Drobot D.V. Synthesis, thermal properties, and growing of strontium and lanthanum aluminates and gallates and the phases on their basis
Oxalate codeposition following by heat treatment was used for synthesis of SrLaAlO₄ and the cryochemical method was used for synthesis of SrLaGaO₄ and SrLaAl_xGa_1-xO₄. The formation of a continuous series of solid solutions in the SrLaAlO₄ -SrLaGaO₄ system was found. SrLaAl_0,2Ga_0,8O₄ and SrLaAl_0,4Ga_0,6O₄ compositions meet requirements to substrates for VTSP films. Heats of dissolution were measured by Calve microcalorimetry, and enthalpy of formation from elements were calculated for SrLaGaO₄ (- 2128,7 kJ/mole) and SrLaAlO₄ (- 2422,9 kJ/mole). Partial pressures of gaseous products for thermal dissociation at T = 1793 K and 1923 K for SrLaGaO₄ and SrLaAlO were calculated. Equilibrium pressures of oxygen are 9,18× 10- ³ and 4,43× 10- ⁴ Pa respectively. The prevailing effect of oxygen on the quality of aluminate monocrystals, particularly strontium-lanthanum gallate has been established.

Bodnar N.M., Yezerskaya N.A., Yenakiev N.Yu. Interaction of iridium (III) sulfide with strong sulfuric acid under heating
Behavior and chemical forms of iridium being generated in high-temperature treatment of Ir₂S_3× 10H₂O by strong H₂SO₄ have been studied. At T = 533-553 K the mononuclear iridium (III) sulfate-complex is found to be generated, which precipitates as a cesium salt Cs[(SO₄)₂(H₂O)₂]. The composition, construction and properties of the complex have been studied by element chemical analysis, electronic and IR-spectroscopy, thermogravimetry, cyclic voltamperometry and coulonometry. A series of thermal stable iridium (III) sulfate-complexes depending on the nature of a second-sphere cation: NH₄⁺ < K⁺ < Cs⁺ is proposed. The rise of initial component interaction temperature up to 583 K is shown to result in the formation of [Ir₃(m ₃-O)(m -SO₄)₆(SO₄)₃]^10- complex sulfate.

Chernyshov V.I., Chernysova O.V., Buslaeva T.M., Drobot D.V. Variants of using electrochemical processes with controllable potential in the technology of precious metals
The application of electrochemical processes with monitoring of the operating electrode potential for extraction and separation of precious metals has been considered as an example of a unique electrochemical processing complex developed. The performances of the complex are given. The different versions of its use are illustrated by the results of separating platinum and palladium during their extraction out of hydrochloric solutions as well as with the data of extraction of gold from spent cyanide electrolytes. Prospective opportunities of the electrochemical complex to produce platinum metal salts are shown.

Buslaeva T.M., Buslaev A.V., Kopylova E.V. Sorption of iridium chlorine-complexes by chemically modified silica
The literature has been examined which concerns sorption of platinum metal complexes and, first of all, iridium complexes chemically modified with silica. Sorption of iridium (IV) and iridium (III) in the form of chloride complexes out of hydrochloric solutions in the static conditions by silica modified with thiourea derivatives has been studied. The effect of medium acidity, temperature, sorption time on the degree of precious component extraction is considered as an example of the sorbent which contains N-allyl-N'-propyl thiourea. It is shown that Ir (IV) is sorbed better then IR (III) irrespective of experiment conditions. The sorption mechanism, which assumes the complexation of iridium ions with an organic molecule fixed on the surface through sulfur and nitrogen atoms, is discussed.

Buslaeva T.M., Sycheva E.V., Kravchenko V.V., Zaitseva M.G. Extraction of palladium (II) out of solutions by extractant mixtures
The extraction of Pd (II) out of hydrochloric and nitric solutions by mixtures of reagents (vol. %): Acorga + 5 % TOA + 9 % IOA (mixture I) and 10 % ABP + 20 % TBP (mixture II) has been studied (here TOA is tri-n-octylamine, IOA is isooctyl alcohol, ABP is alcyl benzophenonoxyme). It was found that the use of these salts makes it possible to significantly expand a range of initial aqueous phase acidity (0,5 t o 9 M) as compared to individual extractants. The synergic factors are estimated for extraction of Pd (II) out of 1 M HCl: 1,9 (mixture I) and 2,0 (mixture II). Based on IR and electronic absorption spectra of organic phases upon extracting by mixture I, a conclusion is drawn about the mechanism of the process consisting of substituting inorganic ligands in extractable alcylammonium complex for molecules of oxyoxymes following by extraction of the complexes of (TOAN)[PdX_n-yR_y] composition into the organic phase, where R is ABP or Acorga, X is acidoligand.

Metal Forming

Solomonov K.N., Kostarev I.V., Kostarev V.I., Listrov E.A. Plotting the boundary line of metal flow in particular case of setting of a part contour
Ratios for determining the position of metal flow boundary line, being as a locus of points equidistant from a part contours, have been derived. The simplest lines and their combinations: a straight line and a circular arc were chosen as a contour. The ratios derived make it possible to plot current lines along which metal is spread over the surface of die impression and consequently to determine metal quantity to flow through the contour. The decision can be of more general character if an arbitrary contour is considered as a line consisting of sections of straight lines and circular arcs.

Physical Metallurgy and Heat Treatment

Medvedeva S.V., Aksenov A.A., Yegorushkina Z.F. Study of interaction along the boundary surface in composite materials on the basis of Al-Zn and Al-Zn-Mg-Cu alloys strengthened by long-measuring coreless fibers of silicon carbide
The kinetics and phase composition of reaction products in composite materials Al-SiC with additives of zinc up to 6 % have been studied by X-ray phase analysis, quantitative metallography, and scanning electron microscopy. In the composite materials, an incubation period of 1,0 duration was observed at T = 700 ° C and 800 ° C and that of 0,5 h duration was observed at T = 900 ° C. Introduction of zinc is shown not to affect the phase composition of the reaction products in Al-SiC composite materials.

Structural macrokinetics self-propagating high-temperature synthesis

Levashov E.A., Kudryashov A.E., Pityulin A.N., Borovinskaya I.P. Features of the effect of additives of superdispersed diamond on the burning processes and structure formation of SHS-systems
The effect of nanocristalline component of exothermic charge (superdispersed diamond powder) on macrokinetic features of burning process of promising STIM grade SHS-materials (Ti-B, Ti-Cr-C-Ni, and Ti-Ta-C-steel systems) has been studied. The structure formation of diamond-bearing SHS-materials has been examined. The effect of modifying the structure of studied materials when introducing the excess of superdispersed diamond was established. The properties of promising SHS-materials were investigated.