Voprosy khimii i khimicheskoi tekhnologii (Issues of Chemistry and Chemical Technology)

10-13

Authors: N.M. Velikonskaya, V.V. Velichko, E.A. Lominoga

In this paper the interaction of scandium(III) ions with salicyl fluorone in the presence of cationic surfactants, nonionic ethoxylated alcohols and their anionic derivatives was studied by spectrophotometric method. It was stated that the optimum pH region is from 2.5 to 7.0. The composition of the complexes Sc–R formed in the presence of surfactants was determined. The results showed that the ratio of Sc:R = 1:2 in the presence of the surfactants differed from that Sc:R = 1:1 which was established in case of the stabilization of the complex with gelatin. In the presence of the surfactant the solution was stable for 20 hours or more. The instability constants have been calculated. It was shown that the instability constants weakly depend on the length of the alkyl radical of surfactant; however, decreasing the degree of ethoxylation results in a substantial increase in the molar extinction coefficient. We determined the concentrations region where Beer's law holds valid (1.410-7–17.110-7 mol/L) and the molar ratios of light absorption of scandium salicyl fluoronats. The use of surfactants resulted in an increase in molar extinction coefficient of 3.5 – 4 times, thus improving analytical possibilities of their application.

21-25

Authors: A.A. Golichenko, S.Y. Treyak, A.V. Shtemenko

The antiradical activity of cis-tetraсhlorodi-μ-carboxylate of dirhenium(III) in various solvents was studied by electron spectroscopy. Carried investigations of interaction of 1,3,5-triphenilverdazile radical with Re2(CH3COO)2Cl42DMSO as an example in 1,2-dichloroethane showed that dirhenium(III) complex compounds with the saturated aliphatic acids are able to neutralize multiple excess of free radicals passing through the step of formation of the intermediate state "complex of rhenium(III) – radical". The use of similar Re26 + derivatives with ligands which contain π-bond (ferulic, indolile-3-acetic acid) causes stabilization of transition state "complex of rhenium(III) – radical" structure. It is shown that the rate of free radical destruction depends on the nature of the solvent. Solvating ability of methanol causes decrease of stability of intermediate state "complex of rhenium(III) – radical" and increase of rate of radical destruction.

32-35

Authors: D.O. Kolomieitsev, S.A. Varenichenko, V.O. Astakhina, V.I. Markov, S.I. Kovalenko, O.V. Kharchenko

Sulphur-containing fused pyrimidines, in particular thienopyrimidines, exhibit wide spectrum of biological activities which stimulates investigation of synthesis and reactions of these compounds. Our previous studies on new series of R1,R2-thieno [2,3-d] pyrimidine-4(3H)-one, thio(seleno)ne derivatives showed that some of obtained compounds have good antimicrobial activity. Another derivative of benzothieno [2,3-d] pyrimidine, 4-hydrazino-5,6,7,8-tetrahydro [1] benzothieno [2,3-d] pyrimidine 3, contains several reactive centers and the heterocyclization reactions can occur in different directions depending on the nature of cyclizing reagents. This paper reports the result of interaction of different dicarboxylic acid anhydrides (maleic, phthalic and endic anhydrides) with the multifunctional compound 4-hydrazino-5,6,7,8-tetrahydro [1] benzothieno [2,3-d] pyrimidine 3 to form novel heterocyclic compounds. The intermediate compounds of cyclization have been identified. The reaction was stated to occur either with intramolecular nucleophilic addition (for maleic anhydride) or with the formation of imid derivatives (for phthalic and m-nitrophthalic anhydrides) depending on the nature of dicarboxylic acid anhydride. The interaction of hydrazine 3 with endic anhydride occurs in one step. The new compounds were characterized by 1H NMR spectroscopy, mass spectrometry and elemental analysis.

45-51

Authors: R.V. Smotraiev, Ye.A. Manidina

The absorption kinetics of sulfur oxide(IV) by solutions of iron(II) and iron(III) salts was investigated. It was found that the absorption of sulfur oxide(IV) by solutions of iron(II) and iron(III) salts in the diffusion region proceeds in two stages: the first stage occurs by the absorption mechanism with a rapid irreversible reaction in the liquid phase; the second stage occurs via the absorption mechanism with a reversible reaction in the liquid phase. The main kinetic characteristics of the process were determined: the rate constants of absorption process for both stages; apparent activation energy and pre-exponential factors for each stage as follows: E1 = 14.26 kJ mol-1, K01 = 0.05 s-1, E2 = 9.01 kJ mol-1, and K02 = 0.01 s-1, respectively. The temperature coefficient of absorption rates is in the range of 1.04 to 1.3. The values of rate constants at the first stage of the absorption process are 1.2 to 1.7 times more than the rate constants on the second stage of the absorption process. The absorption rate of sulfur oxide(IV) by solutions of iron(II) and iron(III) salts significantly depends on the sparging mode. Thus, it is expedient to carry out the absorption process in the Reynolds number range of 50 to 100, because at lower Reynolds numbers the rate constant is significantly reduced, and for higher values there is a significant spray entrainment. The equation of the rate constant dependence for the absorption of sulfur oxide(IV) by solutions of iron(II) and iron(III) salt on the temperature and the gas-phase flow mode was determined.

57-61

Authors: D.G. Zublev, V.D. Barsky

We investigated the influence of both the air supply to decarbonization and the value of disclosure recirculation windows on the recirculation of combustion products in the verticals of coke oven battery located in the middle of the heating wall. The investigation was performed in a production environment. All measurements were carried out at the recirculation windows opened by 100% and 50%. The contents of oxygen and carbon monoxide in the samples of the combustion products taken from the recirculation windows from the vertical downward flow exceed the content of these gases in the samples collected from vertical upward flow. This indicates the presence of a so-called "short circuits" in the heating channels: instead of feeding the combustion products from the vertical downward flow in the vertical upward flow of coke oven gas and air from the vertical upward flow through the recirculation box arrives in a vertical downward flow. The presence of "short-circuit" is also confirmed by measurements of pressure drop. In all cases pressure was higher near the recirculation windows in the vertical of the upstream than in the vertical of the downstream, which is consistent with the results of analysis of the combustion products composition.

68-73

Authors: I.M. Kas'yanenko, V.Yu. Kramarenko

The influence of pigment volume concentration (PVC) and pre-treatment conditions on the vapor and liquid water permeability of a coatings based on aqueous acrylic dispersion Acronal 290D has been studied by international standard methods. These parameters show that water is penetrated through coatings more quickly with increasing PVC. The Nielsen's model for the permeability of the systems containing porous aggregates of filler particles has been used and the fitting parameters were determined. Based on a very sharp PVC dependence and very low values of exponent parameters, it can be concluded that filling of water-based coatings facilitates water migration similar to the channel type diffusion. Increasing of pre-treatment cycles number results in the reduction of permeability that can be related to the enhanced efficiency of coalescence process due to higher temperature conditions at drying of coatings. The PVC effect on the class of coatings in coordinates of the Kunzel's diagram has been also demonstrated.

79-80

Authors: A.O. Omel'chuk, O.A. Pivovarov, A.V. Kravchenko, F.I. Danilov, A.V. Shtemenko

Doctor of Science, Academician of National Academy of Sciences of Ukraine, Professor Volkov S.V. passed away on March 9, 2016. The article highlights the path of Academician Volkov S.V. in science and his contribution to modern inorganic chemistry.