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The phase composition of the interaction product of zinc acetate with hydrogen peroxide in a dispersed aqueous phase of a reverse micellar solution based on oxyethylated Brij 30 surfactant and decane as a dispersion medium is analyzed by powder X-ray diffraction (XRD). Along with ZnO2 nanoparticle, the isolated product is found to contain needle-like microcrystals that, according to the single crystal XRD analysis, are zinc lactate dihydrate [Zn(lact)2(H2O)2]: a = 6.0196(3) A, b = 11.9068(4) A, c = 14.3878(7) A, Z = 4, space group P212121. The coordination environment of the Zn atom is a distorted octahedron: Zn–О distances are 2.051(2)-2.099(3) A, ∠О–Zn–О bond angles are 76.16° and 76.14°. Chelate rings are bent along the О…О line at 22.18° and 11.54°. The Hirshfeld surface (complex sphericity 0.79, asphericity 0.16) is constructed and intermolecular contacts are analyzed. A comparative crystal chemical analysis with the known [Zn(lact)2(H2O)2]·H2O structure is performed.

The deposition of coatings of Au and ZnO nanoparticles (NPs) on glass, semiconductor silicon, polyethylene terephthalate, and polystyrene substrates was studied. Deposition was carried out using relatively concentrated dispersions of particles in ethanol (approximately 5–10 mM Au, ZnO), which showed limited time resistance to coagulation and sedimentation, but returned to their original dispersed state by ultrasonic treatment before each cycle of deposition of NPs. The NPs of Au and ZnO were stabilized by abietate and acetate ions, respectively. Simple coatings from Au or ZnO NPs and a combined coating from a mixture of Au and ZnO NPs, as well as two-layer combined coatings with alternating layers of Au/ZnO and ZnO/Au NPs, were obtained by drop casting and the proposed method of deposition from the capillary layer of the dispersion with the use of a linker. The formation of coatings on transparent substrates was studied by means of UV–Vis spectroscopy. Coatings were characterized by SEM, EDX, XRD, PL, UV–Vis and surface resistance methods. The effect of heat treatment on coatings characteristics was tested.

We studied the usefulness of dispersions of gold nanoparticles (Au-NPs) stabilized by abietic acid for manufacturing films on glass and silicon substrates and composites with nanosized and powder materials exemplified by SiO2 and TiO2 NPs, expanded graphite (EG), carbon nanotubes (CNTs), a porous carbon material (PCM), PCM containing 6% nitrogen, and CeO2 powder.

Comparison of extraction properties of macrocyclic calix[4,6]arenethiaethers (CATE) with their acyclic analogs R2S (R = C6H13, C8H17) for the recovery of [Rh(NO2)3(H2O)3]0 rhodium form from nitric acid solutions was carried out. Rhodium recovery with CATE (0.05 M) in the absence of accelerating additives under optimal conditions exceeds 90% at 5–10-fold preconcentration and is only 1–3% for R2S (1 M). Extraction kinetics was studied and hypothesis on the mechanism of multiple acceleration of rhodium recovery was proposed for CATE extraction, the mechanism includes the formation of intermediate product of colloidal- chemical nature on account of the surface activity of the macrocycle and its reaction with rhodium accompanied by rhodium chelation to the sulfur atoms of neighboring fragments of the macrocycle. The obtained results are of interest for the development of methods for the isolation of fission rhodium from nitrate–nitrite nitric acid solutions.

Hydrophobic gold nanoparticles were prepared via the reduction of HAuCl4 by sodium borohydride in the presence of abietic acid (AA) in nonaqueous polar media based on dimethylformamide (DMF), dimethyl sulfoxide (DMSO), ethanol, and isopropanol. The particles prepared in DMF had spherical gold cores, with a narrow size distribution and the average diameter dAu = 7.1 ± 1.0 nm, and a protective shell formed of abietic acid anions and sodium cations. A violet nanoparticle sediment separated by centrifugation was stored under DMF and could be used for preparing colloidal dispersions of nanoparticles in polar solvents. Ethanol dispersions of nanoparticles were most resistant to sedimentation. The nanoparticles were shown to be useful for sensing nonaqueous polar media.

A comparison was made for extraction systems based on the mixtures of calix[n]arenes phosphorylated at the upper and lower rims (PCA, n = 4 and 6) with dioctyl sulfide (DOS) for recovery of rhodium in the form of [Rh(H2O)3(NO2)3]0 from acid nitrate-nitrite media. Because of inertness of rhodium compounds, the main attention was devoted to extraction kinetics. The kinetic efficiency of DOS + PCA systems was found to be much higher than that for DOS alone, whereas the components of the mixtures do not extract rhodium. Alkyl(ethyl)calixphosphine oxides are the most promising, they behave as accelerating additives in extractant mixtures. Extraction kinetics of [Rh(H2O)3(NO2)3]0 species was studied and extraction systems were selected to develop method for the recovery of fission rhodium.

The crystals of the [Pd3(μ-OH)(μ-CH3COO)5] complex are obtained and characterized using powder and single crystal X-ray diffraction and IR spectroscopy. The crystal structure (a = 15.6942(6) A, b = 11.7190(3) A, c = 9.7871(3) A, V = 1800.05(10) A3, space group Pna21, Z = 4) is formed from neutral trinuclear cyclic molecules of [Pd3(μ-OH)(μ-CH3COO)5], in which the OH− group, together with five CH3COO− anions, is a bridge ligand.

The products of the extraction treatment of Rh(III) and Pd(II) nitrate-nitrite solutions are studied. The [Rh(Thio)6](NO3)3·3H2O and [Pd(Thio)4](NO3)2 complex salts are extracted and an X-ray diffraction analysis of single crystals is performed (BRUKER X8 APEX automated diffractometer, MoKa radiation, graphite monochromator, two-dimensional CCD-detector). [Rh(Thio)6](NO3)3·3H2O crystallographic characteristics are as follows: a = 15.1857(3) A, b = 10.7292(2) A, c = 18.8524(4) A, β = 105.165(1)°, P21/c space group, Z =4; [Pd(Thio)4](NO3)2: a = 5.8013(4) A, b = 7.0981(5) A, c = 11.4991(8) A, α = 99.963(2)°, β = 101.410(2)°, γ = 102.229(2)°, P —1 space group, Z = 1.

We studied nonequilibrium distribution of inert rhodium(III) in extraction by dihexyl sulfide (DHS)and alkylanilinium nitrate mixtures from joint nitrate solutions of triaquatrinitrorhodium (0.1–4 g/L Rh) and palladium (0–2 g/L Pd). We discovered the effect of increasing rhodium recovery in the presence of palladium. This effect has a kinetic nature and arises from the fact that bis(alkyl sulfide) palladium(II) species catalyze the reaction between dihexyl sulfide and a rhodium intermediate based on alkylanilinium nitrate micelles. Depending on initial rhodium and palladium concentrations, the extraction system provides effective distribution factors for rhodium in the range DRh* = 8−300 and rhodium recoveries of 43–97% with ∼100% palladium recovery; single 5-min phase contact at 35°C ensures the 10-fold concentration of both metals in the extract. Our results are useful for developing processes for recovering fission rhodium from spent nuclear fuel.

Using the methods of X-ray photoelectron spectroscopy (XPES), X-ray phase analysis, gamma-resonance (Mossbauer) spectroscopy, thermogravimetry of solid samples and atomic absorption, and atomic emission spectroscopy for solutions, the forms of occurrence of nonferrous metals in oxyhydroxide sediments (nitration hydroxides, NH) from nitration of refining of rhodium, iridium, and ruthenium are investigated. According to the XPES data, nitration hydroxides involve oxidized and unoxidized (selenium) transition metals, namely, Fe(III), Sn(II), Te(IV), Cu(I), Cu(II), Ni(II), Pb(II), As(III), Se(0), and Se(IV), as well as nonmetals O, Cl, and C. All nitration hydroxides are formed mainly by an X-ray amorphous phase (>90%). During heating of nitration hydroxides up to t = 900°C in an inert atmosphere, dehydration of hydroxides and crystallization of certain phases take place, but the X-ray amorphous phase amounts to more than 50%. Purely oxide phases or mixed oxide phases Fe3O4, SnO2, CuIFeIIIO2, and Pb2O3 (NH-1); Ni0.4Fe2.6O4, CuIFeIIIO2, and CuNiSnO4 (NH-2); and Fe3O4, Fe2O3, and SnO2 (NH-3) are formed in this case.

The dissolution of silver nanoparticles in their reaction with aqueous HNO3 solubilized to an reverse micelle solution of sodium bis(2-ethylhexyl)sulfosuccinate in decane is studied spectrophotometrically. A physicochemical model is advanced for quantifying the process kinetics on th basis of the following autocatalytic scheme: Ag0 + H+ + NO 3 − → Ag+ + products (k 1), and Ag0 + Ag+ + NO 3 − → 2Ag+ + products (k 2). The effective rate constant k 2 decreases with decreasing solubilization capacity V S/V O (where V S is the volume of the solubilized dispersed aqueous phase and V O is the volume of the micelle solution); the solubilization capacity determines the size of the micelle cavities in which the reaction between Ag0 and HNO3 occurs: k 2 = 74 (V S/V O) · 100% ≈ 3.8%), 41 (2.9), and 35 (2.0) L/(mol s). The effective constant k 1 is determined with a high uncertainty; the effect of V S/V O on k 1 has the opposite tendency.

The manifold enhancement of the rhodium extraction efficiency from nitric acid solutions of triaquatrinitrorhodium is discovered with the use of two-component mixed extractants based on alkylaniline (AA), dihexyl sulfide (DHS), dihexyl sulfoxide (DHSO), tributyl phosphate (TBP), and oxime ACORGA P5100. A mixture of unimolar solutions of alkylanilinium nitrate and DHS is found to be the most efficient extractant: at 35°C, this mixture quantitatively extracts rhodium within 5 min from aqueous solutions containing 0.06 to 3 mol/L HNO3. The extraction kinetics are studied. The following two-stage extraction mechanism is substantiated: the equilibrium of formation of a colloidal-chemical intermediate involving [Rh(H2O)3(NO2)3], HNO3, and (BHNO3)p (an associated form of the alkylanilinium salt) and the reaction of the intermediate with DHS (the rate-controlling stage).

The growth kinetics of silver nanoparticles upon silver(I) reduction with sodium citrate in an aqueous solution solubilized to a reverse micellar solution of sodium bis(2-ethylhexyl) sulfosuccinate in decane is studied spectrophotometrically under constant conditions of irradiation of the reaction mixture with visible light. The formal kinetics of the process corresponds to an autocatalytic mechanism. The effective rate constants of growth of silver nanoparticles, unlike those of gold nanoparticles, are independent of the size of the inner micellar cavity when its radius changes from 2 to 6 nm. This is most likely due to a great effect of the photochemical factor or Ag+ localization in the inner surface layer of the micelles on the rate constants.

Single crystals of the [PdL2(NO2)2] complex were obtained for the first time, where L is di-n-butylsulfide. Single crystal and powder diffraction studies provided new data on the molecular and crystal structure of this compound.

In order to use low-level fission palladium in technology, the paladium must be purified to a high degree with respect to foreign radionuclides with close chemical properties—ruthenium, antimony, and silver. The results of a simulation of an optimized two-cycle extraction scheme for extracting and refining palladium on the basis of one extractant—an aromatic solution of petroleum sulfides: first cycle with nitrate and second cycle with chloride system—are examined. The behavior of trace concentrations of silver is investigated and it is shown that total deep removal of silver from palladium of not less than 4.107–40 in the first cycle and 106 in the second cycle with a small number of extraction, washing, and reextraction steps can be attained. 2 figures, 3 tables, 6 references.

The experimentally determined total purification factors for palladium relative to silver (first cycle 102, second cycle >103) and rhodium and ruthenium (first cycle >104, second cycle >10) are greater than 105. In connection with the insufficient sensitivity of the atomic absorption method for monitoring and the relatively high value from the control run, we could not determine the true values of the purification factors in some operations of the second extraction cycle and for precipitation of palladosammine. The noted chemical aspects of the behavior of precious metals in extraction systems with petroleum sulfides lead to an estimate of the purification factors for palladium at the 108 level. In particular, the total purification factors increase by 10–100 times when the extraction is carried out in both cycles with W:O=10:1 (F=(W:O)/Dj, where j is the component to be separated [10]). Larger-scale laboratory testing of the proposed flow diagram for recovery and refining of palladium using Ag, Pd, Ru, Rh, and Sb will allow us to experimentally confirm that such estimates are realistic.

The article summarizes experiments performed on the extraction of palladium from spent nuclear fuels. Palladium extraction from high-level nitric acid solutions was performed using diesel fuels and petroleum sulfides. Petroleum sulfide extraction systems with aromatic solvents provided the highest selectivity for palladium. Experimental results for refinement of palladium after extraction are also summarized. 14 refs., 4 tabs.

A method for the preparation of [Pd(NH3)4Cl2]Cl2 through the oxidation of [Pd(NH3)4]Cl2 with a mixture of HCl and HNO3 acids (3 : 1) in an aqueous-ammonia solution was proposed. The composition of the product was confirmed by X-ray diffraction and chemical analyses and IR and Raman spectroscopy. The yield of the product was higher than 90%, and the content of the main substance was estimated as at least 95%. The crystallographic parameters of [Pd(NH3)4Cl2]Cl2 were determined. The salt was found to be isostructural to Gros salt [Pt(NH3)4Cl2]Cl2.