A structural formula and quantum-chemical characteristics of the most energetically probable stable conformation of a bioreagent molecule, which is formed upon oxidizing iron(II) ions by Acidithiobacillus ferrooxidans autotrophic mesophilic iron-oxidizing bacteria in a sulfuric acid solution consisting of iron(III) ions and three acidic residues of glucuronic acid, are determined. The bioreagent oxidant is widely applied in industry for leaching metals from sulfide ores of nonferrous metals and concentrates of concentration. Quantum- chemical characteristics of the bioreagent molecule are analyzed in comparison with anhydrous iron(III) sulfate, which is also used in hydrometallurgy as an oxidant. To investigate the structure and quantum- chemical characteristics, the molecular computer simulation method, the theory of boundary molecular orbitals, and the Pearson principle are used. It is established that the most energetically probable stable conformation of the bioreagent molecule contains acidic residue of glucuronic acid with a noncyclic structure. According to the results of investigations, the bioreagent is referred to more rigid Lewis acid (the electron acceptor) than Fe 2 (SO 4 ) 3 . The bioreagent molecule is less polarized and has lower absolute electronegativity and a twofold larger volume. The theoretical substantiation of the larger persistence of primary sulfides (pyrite, pentlandite, and chalcopyrite) relative to secondary minerals (pyrrhotine, chalcosine, and covellite) is proposed based on calculated values of boundary molecular orbitals; absolute rigidity; and the electronegativity of iron, copper, and nickel sulfides. Characteristics determining the interaction efficiency (volume, heat of formation, steric energy and its components, total energy, etc.) of the bioreagent are multiply larger than for Fe 2 (SO 4 ) 3 . The larger oxidative activity of the bioreagent relative to Fe 2 (SO 4 ) 3 can be substantiated by a higher partial charge of the iron atom and a longer bond length between the atoms, the lower energy of the lowest free molecular orbital, and increased degree of the charge transfer during the bioreagent interaction with sulfide minerals.

3D models of clusters of antimony and bismuth sulfides were constructed. For these models, the charges of individual atoms and the electron populations of s-Pop, p-Pop, and d-Pop orbitals were determined. Collector activity evaluation prediction (CAEP) was made for a number of proposed reagents attached to atoms of clusters of minerals. CAEP characterizes the activity of a collector: the lower CAEP, the more preferable the interaction of the collector and the more efficient the flotation reagent. For flotation of antimony and bismuth minerals, a number of promising collectors were recommended.

Molecular modeling has experienced constant and considerable development over the past ten years in India, China, Turkey, Russia and Finland. In the present study computational modeling of minerals and reagents was performed using Chem Bio 3D and ChemOffice2005 by CambridgeSoft with optimization by MM2. The semi empirical calculations were provided by MOPAC. Molecular structures of antimony clusters were created. DTF approach was used to determine energies such as HOMO, LUMO and SOMO. Absolute hardness. and chemical potential. by Pearson and Parr have been calculated. The strategy of prognosis of collector activity evaluation (PCAE) has been proposed as a consistent approach to estimate the interaction between a collector and a mineral cluster as a difference of total energy and sum of cluster energy and collector energy. The lower PCAE the stronger the ability of the collector to interact with the mineral cluster. Although PCAE cannot play the role as an indicating physico-chemical parameter for the particle floated but allows to make some significant conclusions. To improve the separation of minerals the method of complex formation between collectors and mineral clusters was harnessed. The main physico-chemical parameters have been determined. The probable increasing collecting ability of sulfhydril collectors for stibnite follows the order as : butyl xanthic acid (BXA), dimethyldithiocarbamic acid (DMDTCA), piperidine dithiocarbamic acid (PDTCA), mixture of butyl xanthic acid and dithiocarbamic acid (BXA+DTCA), Bis(2(dibutylamino)ethyl)dithiophosphonic acid (DBAEDTPA) and diethyl aminoethylxanthic acid (DEAEXA). Dialkylamino sulfhydril collectors may be considered to be prospective reagents for sulfide ore flotation. The results obtained were confirmed by experimental data in ore flotation.

Physicochemical representations and computer modeling are a promising direction in the selection and application of more effective reagents when solving the problem of the complex use of ores. In this publication, results of the investigation into the interaction of sulfhydryl collectors with antimony sulfide and evaluations of the interaction mechanism of these reagents with antimonyl (the main product of oxidizing antimonite) using the ChemiBi3D program of the ChemOffice specialized complex of the Cambridge Soft corporation (Great Britain) as well as the MOPAC 2012 program module (United States) are given. The possibility of applying a series of indices, which are computer characteristics of reagents, as the criterion of evaluating the flotation activity of organic compounds relative to nonferrous metal cations is substantiated.

The O,O′-diethyl dithiophosphate complex of tetraphenylantimony(V) [Sb(C 6 H 5 ) 4 {S 2 P(OC 2 H 5 ) 2 }] ( I ) and its benzene-solvated form I · 1/2C 6 H 6 ( II ) were synthesized and studied by high-resolution solid-state 13 C and 31 P NMR (MAS NMR). The diethyl dithiophosphate (Dtph) groups in I and II were quantitatively characterized by the 31 P chemical shift anisotropy (δ aniso ), the asymmetry parameter (η), and the principal values of chemical shift tensors (δ xx , δ yy , δ zz ). The calculation of the anisotropy parameters included construction of χ 2 statistic diagrams from full 31 P MAS NMR spectra. In both complexes, the Dtph groups were found to have mainly axially symmetric 31 P chemical shift tensors (for δ zz < δ xx ≈ δ yy ) with similar anisotropy parameters (δ aniso and η), which is due to their identical S-monodentate function. According to X-ray diffraction data, II has a trigonal bipyramidal (TBP) molecular structure with Smonodentate coordination of Dtph in the TBP axial position and outer-sphere position of the benzene molecule. The desorption of the outer-sphere benzene solvent molecules from structure II , which was noted in MAS NMR experiment, passes through the formation of three intermediate solvated forms with benzene content n < 1/2.

The authors have carried out molecular modeling of clusters of simple structure and ring structure pyrite. It is suggested to analyze bonding of a collecting agent and cluster atoms using the collector capacity forecasting index. It is shown that butyl dixanthate more vigorously connects to cluster atoms than thionocarbamates, e.g., Z 200 and IETNC. Analysis of the charge transfer during interaction of pyrite with the listed collecting agents shows that in monodentate bonding the charge is transferred from the mineral to the collector sulfur atoms and in bidentate bonding the classical transfer of the charge from the collector donor to the mineral acceptor is observed. It is supposed that ferrum xanthate decompounding in an acid medium results in inception of dixanthates that govern pyrite flotation. Pyrite oxidation and elemental sulfur formation also favor pyrite flotation but complicate pyrite depression in an alkaline medium.

Fatty acids modified by sulfhydric collectors are investigated. Three-dimensional molecular models are constructed for these acids and the main computer parameters of the total steric energy are determined. Based on the computer design, new reagents are suggested and molecular models are constructed and the total steric energy is calculated for them.

Computer simulations of sulfhydryl collectors and their derivatives are performed for the first time using the Chem3D program of the ChemOffice specialized software package. Models (ball-rod and spatially filled) for sulfhydryl collectors and short-chain carboxyl acid modified by dithio groups are constructed. Effective collectors for sulfide ores are proposed, based on the concepts of the coordination theory of flotation. The interaction of reagents with a surface of sulfide and oxidized minerals is interpreted. The results from the flotation of ores using modified reagents are presented.

The authors have built ball and stick and Stuart-type molecular models of some disulfides of thiphosphoric acids and sulphydryl collectors, determined basic parameters of molecules, such as dipole moments and limit electron densities NMR(1) H and NMR(13)C, and analyzed flotation properties of disulfides of sulphydryl collectors.

Stereochemical representations about molecules flotoreagents are considered. The computer technology and chemical programs for visualization of three-dimensional model of a molecule sulphydrylic collectors and their complexes with tetraphenylantimony (V) is used: Ball and Stick, hemispherical Stuart-Brigleba.The way of updating sulphydrylic collectors carboxyl by acids and tetraphenylantimony (V) complexes is developed. Efficiency short chains carboxyl the acids modified by duthio fragments at flotation copper and gold-bearing, polymetallic ores in a mix with sulphydrylic reagents is shown. At application of a combination of reagents it is observed synergism.

The article presents results of hydrometallurgical and bio-treatment of antimony ores and recommend new dissolvents for antimony sulfides. The authors introduce a processing plant which is a single operating processor of antimonic gold-bearing alloys with the successful electrolytic refining of anodes and production of cathode antimony and noble metal slurry in Russian Federation.

An analytical review of the main gold-antimony ores in the Russian Federation is presented. The practice is shown and the results of the concentration of Au-Sb ores in the Sarylakh, Sentachan, and Maltan deposits (the Sakha Republic (Yakutia)) are presented. A series of selective reagents for the flotation of antimonite from complex gold-antimony ores is considered. The data of industrial tests using sodium dimethylthiocarbamate in processing the gold-antimony ores are presented and its efficiency is shown.

Published data on the effect of lead(II) compounds on the kinetics of dissolution of metallic gold and its extraction from ore materials and concentrates are considered.

The results of arsenic removal from water sources to a residual concentration of <10 μg/l are presented. The main physicochemical parameters were established for the As removal by polystyrene, modified granules of a poly VVFE polymer, and iron hydroxide-coated calcium alginate granules. It is shown that adsorptive filtration is the effective method for arsenic removal.

The sorption activity of biomass with various substance composition is estimated relative to ions of nonferrous and noble metals. The possibility is shown for the effective extraction of metals by biosorbents with subsequent biomass flotation. The influence exerted by a number of technological and physicochemical factors on the flotation indices is established. The combined technological scheme is recommended for realization.

The original method is developed for producing the new inorganic sorption material of akaganeite bgr-FeO(OH). The material in question is characterized relative to arsenic contained in aqua. The possibility is established for removing arsenate ions from water by contemporary physicochemical methods.