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Organic synthesis products are widely used in the daily life beginning with medicinal, sweet preparations, lacs, dyes up to plastic, rubber, etc . Benzene that is amongst the top ten largest of the biggest substances of the chemical industry being highly liquid and high priced products. In this regard, this product is manufactured both at petrochemical enterprises and their by-product coking plants. Coal crude benzene contains unsaturated and sulphur compounds and it is required to preliminarily purify it from these undesirable impurities to obtain pure products from it. Even insignificant amounts of sulphur in benzene and toluene when using them in organic synthesis processes cause fast poisoning of the catalyst, and resinous substances formed resulting from polymerization of unsaturated compounds cover the catalyst surface and thereby deactivate it. Analysis of the published works on purification methods of coal crude benzene from unsaturated and sulphur compounds was performed in the present review. The advantages and shortages of the known methods were considered. Prospects of ozonolytic purification of coal crude benzene were demonstrated.

Tellurium reduction in alkaline solutions in the concentration range of tellurite ions of 0.001-1 М was studied by a voltammetric method on updated solid indicator electrodes (Au, Pt, Ni and graphite). It was detected that a change in the form of the cathode current-potential curve was observed for all electrodes at constant alkali concentrations and an increase in the tellurium concentration in solutions above 0.2-0.3 М. It was found that a change in the ratio of hydroxide and tellurite ions concentrations could be one of the probable causes for this. An opportunity of using the studied electrodes for express control of the tellurium concentration in the alkaline electrolyte used to obtain high purity tellurium was demonstrated.

Samples of an Al-Fe alloy of composition of (2.15±0.08) mass %, admixtures of not more than 0.2 mass %, were studied. It was demonstrated by XPA that the intermetallide of composition Al_3.2Fe and polycrystalline aluminium were formed at alloying of metals. The interaction of Al-Fe alloy samples with liquid Ga-In eutectics was studied by methods of scanning electron microscopy and energy-dispersive X-ray spectroscopy. It was found that an Al-Fe alloy became activated slower by liquid Ga-In eutectics than polycrystalline aluminium and Al-Ni alloys. The intermetallide phase of Al_3.2Fe composition does not undergo significant chemical changes. It was demonstrated by multiple frustrated total internal reflection IR spectroscopy that aluminium chloride complexes of various compositions were in situ formed during the interaction of activated samples of an Al-Fe alloy with tert-butyl chloride. The complexes showed catalytic properties.

The preparation of new derivatives of polysaccharides showing the biological activity, precisely, antimicrobial properties remains quite a priority task not only in chemistry of high- molecular compounds but also in pharmaceutics and medicine, since some antimicrobial compounds obtained on the basis of natural polymers are superior to synthetic low-molecular weight antimicrobial compounds on some criteria. New water soluble pectin derivatives containing sulphamic groups in their structure were obtained in this work by the interaction of sulphamic acid with polysaccharide aldehyde groups. The structure and composition of the resulting compounds were studied by IR spectroscopy, elemental (nitrogen, sulphur) and X-ray crystal analyses. Sulphamic pectin derivatives with various contents of sulphamic groups were obtained by changing the concentration of sulphamic acid in relation to dialdehyde pectin derivatives. The optimum ratio of reactive components that is -СНО/NH₂SO₃H = 1.0 : 2.5 and the reaction time of 45 min were found. Study results of antimicrobial action of antimicrobial action of the synthesized sulphamic pectin derivatives were presented. The biological activity of the resulting compounds was studied by the disk diffusion method in relation to gram positive and gram positive negative bacteria. Direct dependence of the antimicrobial activity of the studied preparations on the quantitative content of sulphamic groups in pectin was found. It was determined that sulphamic pectin derivatives with a substitution degree of 35.0 showed antimicrobial activity in relation to Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Proteus vulgaris, Streptococcus faecalis, Streptococcus pyogenes, Streptococcus faecalis, Pseudomonas aeruginosa with a concentration of 50 μg/mL. Antimicrobial action begins to decrease with the decrease in the number of sulphamic groups. Study results of acute toxicity of sulphamic pectin derivatives were presented. According to the results, they can be referred to class V almost nontoxic substances.

The activity in the carbon monoxide (CO) oxidation reaction of МеО _х /М and Pd/МеО _х /Ni-Al/НС catalysts where MeO _x : Al₂О₃, Al₂О₃-СеО₂, Al₂О₃-MnО₂ carrier is applied to Ni-Al/НС (grids made of HC with an evaporated Ni-Al layer) was studied. Samples, in which grids made from fechral and nichrome were used, were prepared for comparison. It was demonstrated that intermediate Ni-Al coating itself serving to increase adhesion of oxides to a metal substrate exhibited the catalytic activity. The most active samples activated and not activated by palladium were determined according to the results of catalytic trials. All catalysts were characterized by X-ray phase analysis, scanning electron microscopy methods. The most active Pd/Al₂O₃/Ni-/HC sample was additionally studied by scanning electron microscopy (SEM) with local analysis.

Potassium sorption processes from aqueous solutions of KH₂PO₄, K₂HPO₄, K₃PO₄, KCl, and KNO₃ by porous substrates of bast and birch bark were studied. The effect of the nature of the salts on potassium sorption was found. It was demonstrated that the investigated salts by their capacity to potassium sorption could be placed in the following row: K₃PO₄ > К₂HPO₄ > KCl > KNO₃ > KH₂PO₄. Comparison of sorption of potassium and phosphates from solutions of phosphorus-containing salts was made. The effect of pH of solutions and the background electrolyte on potassium sorption from various salt solutions was studied. It was found that the application of the background electrolyte exerted a positive effect on potassium sorption from solutions of KH₂PO₄, KCl and KNO₃. It was demonstrated on an example of potassium chloride and potassium nitrate that an increase in the pH of solutions of the salts to 10.7 led to a larger increase in potassium sorption in comparison with the effect reached in the presence of the background electrolyte. It was found that the highest sorption of potassium (А_∞) was reached from solutions of K₃PO₄ and KCl (рН 10.8) and amounts to 32.55 и 30.20 mg/g, respectively. Potassium sorption isotherms obtained under various conditions, for which values of the constant К_L and the limiting sorption А_∞ were determined according to the Langmuir equation, are given. Potassium sorption values were calculated using these significations and compared with the experimental data. It was demonstrated that porous substrates of bast and birch bark showed close sorption activities in relation to potassium. The substrates investigated exceed activated carbon of birch wood.

Assessment of the chemical composition of snow melt water was carried out in the zone of influence of the aerial technogenic load from the largest source of emissions in the territory of the Murmansk Region that is a copper-nickel combine (Monchegorsk area) of the Kola Mining and Metallurgical AO. The results of direct analytical determination in the framework of annual monitoring were complemented by the results of retrospective analysis by means of physicochemical modelling (Selektor program complex). The obtained results testify a change in the deportments of elements in snow melt water when decreasing the level of the multicomponent aerial technogenic load after production modernization. The minimisation of dust emissions and an increase in the efficiency of purification of fume gases from sulphurous anhydride contributed to a shift of the redox potential of snow melt water from the negative to positive region and a transfer of some pollutants elements with a variable valence into the oxidized form. A decrease in dust emissions that exerted the alkalinizing effect contributed to an increase in water acidity and consequently, an increase of the proportion in them of the aluminium ionic form recognized most toxic for biota. The sulphates concentration in the atmospheric deposition of the winter season currently does not go beyond All-Russian weighted average concentrations even in the local area of model objects. Increasing the proportion of copper chloride complexes was noted in snow melt water, a basic pollutant, which testifies a possible increase in its migratory activity that is driven by an increasing effect of sea aerosols when softening the regional climate. The practical significance of the work is expressed in an opportunity to reconstruct element speciation in melt water both during retrospective analyses and planning the procedure of biotesting in engineering and environmental survey and monitoring studies.

Chemical transformations of petroleum extracts of peat wax occurring in the process of mechanochemical treatment (cavitation) of the most typical types of high-moor peat for the territory of Khanty-Mansiysk Autonomous District - Yugra were studied. It was demonstrated that hydrolysis of ester bonds in the composition of wax molecules proceeded in alkaline media resulting from mechanochemical treatment of peat raw materials. Alcohol groups of waxes formed as result of hydrolysis are subjected to oxidation to aldehyde groups followed by condensation. Peat waxes are capable of entering into reactions with ammonia molecules, which is confirmed by elemental analysis results during the processes listed. It was suggested that free-radical states, as well as hydrogen peroxide formed due to mechanochemical treatment of aqueous alkaline media were a source of an oxidizing agent. Additionally, based on elemental analysis data and IR spectra obtained, a hypothesis was put forward of mainly the aldol condensation mechanism for processes initiated by mechanochemical treatment. A preliminary conclusion was made of the fact that only a part of peat waxes participates in the stated processes, which allows using this type of raw materials more rationally, simultaneously obtaining humic acids and bitumenols from it. It was demonstrated that qualitative characteristics of peat wax isolated from oxidative aminolysis products met requirements for technical conditions imposed on raw peat wax.