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Russia is strongly behind the leading oil-processing countries in the production of high-octane nonaromatic components of motor petrol (in particular, isomerizate petrol) from light hydrocarbon raw material. One of the possible means to solve this problem is the use of ZSM-5 type zeolites as isomerization catalysts, which allows the process to be carried out under non-standard conditions: without the admission of hydrogen-containing gas into the reaction medium at atmospheric pressure, without the use of precious metals and superacid additives. In the present work, high-silica zeolite of the ZSM-5 structural type with the silica ratio equal to 40 was obtained by means of hydrothermal synthesis and then modified by nanometer-sized nickel powder. The catalytic activity of initial and Ni-containing zeolites and the dynamics of there deactivation were studied in the transformations of n-pentane, n-hexane, n-heptane, n -octane, a mixture of pentane and hexane and the virgin gasoline fraction of petroleum. It was shown that the major products of the transformation of light hydrocarbon raw material at the catalysts under study are n - and isoalkanes С₄-С₈, alkyl benzenes; naphthenes and olefins are formed in insignificant amounts. Zeolite modification with nanometer-sized nickel promotes an increase in the yield of liquid products with increased isoalkane content and makes the stability higher in comparison with the initial sample. This is due to the presence of active Ni-containing centres in the catalytic system; these centres participate in hydrogenation-dehydrogenation reactions. As a result, the rate of the formation of condensed molecules (which are coke precursors) decreases, and catalyst deactivation proceeds slower. The largest amount of carbon deposits having the dense structure is formed in the conversion of n-octane, while the smallest one is formed in the conversion of n-pentane.

Expanded investigation of the chemical composition of water from melted snow was carried out at the territories under intense technochemic load from one of the largest mining and smelting enterprises of the Murmansk Region - Kola Miming and Metallurgical Company Norilsk Nikel JSC. The data obtained by direct analytical determination were supplemented by the results of physicochemical modeling using the software complex Selektor within the system Al-B-Br-Ar-He-Ne-C-Ca-Cl-F-K-Mg-Mn-N-Na-P-S-Si-Sr-Cu-Zn-H-O-e^– and have practical significance for the reconstruction of changes in the ion composition of the dissolved part of water from melted snow under different technogenic load and for restoration works under the conditions of operating plant.

Changes in the concentrations of ghalogens (fluorine, chlorine, iodine) in soil and in the plants of agrocenosis were studied. It was established that the introduction of fertilizers promotes a substantial (by 29−32 %) increase in the total fluorine content in the upper (0−20 cm) soil layer; the level of water-soluble fluorine increases noticeably within the whole soil layer under investigation (to the depth of 1 m). The introduction of potassium fertilizers causes a substantial increase (by 20−25 %) of chlorine content in the soil of agrocenosis with its uniform distribution over the soil profile. The total level of iodine in the upper soil layer somewhat increased, while the concentration of water-soluble iodine decreased substantially (by 40−50 %). The use of potassium fertilizers in combination with phosphorus-containing ones promotes a decrease in fluorine concentration in vegetable products; the consumption of chlorine and iodine by plants increases substantially under these conditions.

The effect of alkaline and acidic treatment on the properties and texture characteristics of native sapropel from Lake Gorchakovskoye (the Omsk Region) and carbon-mineral materials obtained from sapropel through carbonization was studied. It was established that acidic treatment with low-concentration HCl solutions causes an increase in the total pore volume with respect to water in carbon-mineral materials up to 0.42 cm³/g; the ash value decreases without any changes in bulk density due to the removal of the organic and mienral part in native sapropel. Alkaline treatment with the aqueous solutions of NaOH allows achieving the developed surface in the carbon-mienral materials up to 106 m²/g. The major fraction of pores in the treated carbon-mineral materials is represented by mesopores 3.4−5.4 nm in diameter, and macropores more than 600 nm in diameter.

The distribution of thiocyanate acidocomplexes of a series of metals in layering systems “water - catamine AB - potassium chloride” and “water - oxyphos B - ammonium sulphate” depending on the concentrations of NH₄SCN and H₂SO₄ were studied. The cobnditions for quantitative extraction of copper (II), zinc, iron (III), cobalt were determined. The spectrophotometric characteristics of extractable thiocyanate complexes of Cu(II), Co and Fe(III) were studied. A procedure for extraction photometric determination of cobalt was developed.

More than 150 compounds represented by n- alkanes, n- alkane-2-ones, n- aldehydes, fatty acids and their esters, as well as isoprenoids including sesqui-, di-, triterpenes, steroids, acyclic compounds and tocopoherols were identified in the chloroform-methanol extract of high-moor and valley peat from native, unwatered and recovered regions of marshes in Belarus and in West Siberia by means of gas chromatography - mass spectrometry The composition of carotenoids and tatrapyrrhole pigments was determined in the acetone extract of peat by means of high-pressure liquid chromatography in combination with absorption spectroscopy. Chlorofyll a and b, pheophytin a and b, pheophorbide a, bacteriopheophytin b, lutein, α-carotene and neoxanthine were identified. It was demonstrated that the compounds undergoing the most substantial qualitative and quantitative changes during dewatering are sesqui-, di- and triterpenes, steroids, as well as carotenoids and tetrapyrrholes. Unlike for unaffected peat beds, the dominating sesquiterpene in all the studied high-moor and valley peat samples from dewatered and recovered regions is β-cadinene; the derivatives of lanosterol are present among steroids; in dewatered and recovered valley peat of Belarus there are des-A-derivatives of oleane structures, while among triterpenoids of dewatered peat from West Siberia there are oxygen-containing hopanoids. As a consequence of dewatering, chlorophylls disappear from peat pigments, while the concentration of neoxanthine increases. Dienic pentacyclic structures are absent from dewatered and recovered high-moor peat in Belarus, while the overall fraction of hopanoids increases. As a result of repeated watering of dewatered regions of upland bogs in Belarus, betulin and b-amirin appear among five-membered cyclic isoprenoids. Similarly to native peat, keto derivatives of hopene and oleanene are detected in those samples, while these compounds are absent from peat in dewatered region. The differences in the changes of the individual composition of triterpenes accompanying bog dewatering in West Siberia and Belarus may be due to more severe clinmatic conditions and, as a consequence, low rate of oxidative processes taking place in peat deposit. The obtained results may poromote deeper understanding of the processes that take place in peat deposits, prediction of the development of peat marsh ecosystems and reasonable use of peat.

Precipitation of bismuth (III) tartrates from hydrochloric, nitric and acetic solutions depending on the concentration of tartrate ions and process temperature was studied by means of chemical, X-ray phase, differential thermal analysis, IR and Raman spectroscopy, and electron microscopy. It was demonstrated that normal bismuth tartrate with the composition BiC₄H₃O₆ x H₂O or bismuth tartratahydrotartrate trihydrate with the composition [Bi(C₄H₄O₆)(C₄H₅O₆)] x 3H₂O are formed after the addition of tartaric acid into hydrochloric and acetic solutions of bismuth. Two compounds are formed during bismuth precipitation from nitric solutions with tartaric acid, depending on the concentration of tartrate ions: nitrate-tartrate complex with the composition [Bi(NO₃)(H₂O)₃]C₄H₄O₆ and tartratahydrotartreate trihydrate [Bi(C₄H₄O₆)(C₄H₅O₆)] x 3H₂O. As a result of multiple washing with water, the nitrate-tartrate complex is transformed into X-ray amorphous normal bismuth tartrate with the composition BiC₄H₃O₆ x H₂O. Normal bismuth tartrate is also formed after the addition of sodium tartrate into the nitric solutions of bismuth for the molar ratio of tartrate ions to bismuth equal to 1−3, and process temperature 23−60 °C. With further increase in sodium tartrate concentration in the system, the degree of bismuth precipitatiuon decreases sharply as a consequence of the formation of water-soluble complex ions. It was demonstrated that normal bismuth tartrate BiC₄H₃O₆ x H₂O is identical with the compound known previously as monobismuth tartaric acid. It was shown that the hydroxy bismuth salt of monobismuth tartaric acid, which is obtained by precipitation from lactic-acetic solutions and is recommended as the medical substance of antisyphilitic preparation Bismoverol, is not an individual compound but is a mixture of normal bismuth tartrate with the composition BiC₄H₃O₆ x H₂O and bismuth oxoacetate with the composition BiОC₂H₃O₂.

A novel approach to planning and visualization of the cyclic and isohydric method for obtaining potassium nitrate is considered. The approach is based on the use of the data on phase equilibria in a quaternary mutual water-salt system K⁺, Na⁺//Cl⁻, at different temperatures. A key to process visualization ios the joint plotting of the diagram of state and its isohydric sections corresponding to the compositions of reference points. Experimental material balances are presented for this process carried out using retour of sodium chloride and without it. It is demonstrated that the introduction of retour allows one to decrease the losses of return solution at the stage of sodium chloride isolation, and to use sylvinite as the initial raw material for the process.

It is demonstrated for the first time that the reaction carried out under the conditions of RAPET (Reaction under Autogenic Pressure at Elevated Temperatures) is accompanied by the interaction of polyvinyl chloride (PVC) decomposition products with bulk metal and causes its self-dispersion. Thus formed nanoparticles act as a catalyst on which the growth of carbon nanofibers occurs. The mechanism of this self-dispersion is due to oxidation-reduction transformations participated by the components of reaction medium formed as a result of PVC thermolysis. Technologically easy method to process PVC wastes in the presence of self-organising catalysts is proposed. As a result of this process, the plastic matter is completely decomposed with the formation of carbon nanofibers. The literature data on the catalytic corrosion of bulk metals and alloys are generalized. On the basis of analysis, the optimal process parameters were chosen. The evolution of resulting materials within temperature range 420 to 1000 °С was studied by means of electron microscopy. The morphology of the formed product was studied and its chemical analysis was carried out. The dependence of the chemical composition and morpholopgy of the formed products on synthesis temperature was established. The SEM images of structured synthesis products formed at different temperatures are presented.

The ratings of 100 leading universities of BRICS countries are analyuzed. The positions of Russian Universities are discussed. Attempts are made to reveal the reasons of the existing situation and to determine the actions that can improve the positions of Russian Universities. Siberian universities included into the hundred leading universities under discussion are considered in detail.