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Information × Registration Number 0213U001965, 0111U009943 , R & D reports Title Studies of the catalytic reactions of hydrocarbons and other cokechemistry products for the search of new ways of their use popup.stage_title Head Lobachev Vladimir Leonidovich, Registration Date 18-03-2013 Organization The L.M.Litvinenko Institute of Physical-Organic Chemistry and Coal Chemistry popup.description2 Object of research: the reaction of diethylsulfide (Et2S) with hydrogen peroxide (H2O2) and its the activated forms in water and water-alcohol solutions (H2O / ROH) variable composition. The aim of the research: the study of the influence of composition of the solvent water-alcohol on the kinetics and mechanisms of oxidation Et2S by activated forms of H2O2; the search of optimal conditions of activation of H2O2 boric В(ОН)3 and silicic acids in the reactions of selective oxidation of thioethers. Research methods: the kinetic methods, GLC, pH - metry, quantum-chemical calculations. Additions of B(ОН)3 result in considerable accelerate of oxidation of Et2S by H2O2 in water and in the water-alcohol solutions H2O/ROH (ROH = EtOH, i-PrOH, t-BuOH, HOC2H4OH). A catalytic effect В(ОН)3 is conditioned intermediate equilibrium formation of anions of monoperoxoborate (MPB) and diperoxoborate (DPB). A transition from water to aqueous-alcohol solutions results in the noticeable increase of solubility of Et2S.The rate constants as uncatalytic as catalytic (kMPB and kDPB) routes of oxidation of Et2S go down among НОС2Н4ОН>EtOH>i-PrOH>t-BuOH and with growth of concentration of alcohol in solution, here in all environments of kDРВ>>kMРВ >>kOOH. Most interest presents system ethyleneglycol/water, which the decline of rate constants by comparison to water solutions is the least for, and the catalytic effect of borate is high. DFT-method showed that oxidation of dimethylsulfide (Me2S) by peroxides (ХООН) depending on nature X can flow on two mechanisms. In the reaction of Me2S with the hydrogen peroxide (Х=Н) a direct reagent is a molecule of НООН, and in reactions with mono- (Х=B(OH)3) and diperoxoborate ((Х=B(OH)2OOH) - a reagent is contained by the fragment of "oxide of water" of (Х-(+ОН)-О-). Theoretical ratio of rate constants of reaction Ме2S with Н2О2, МРВ and DPB is 1:4:80, that practically coincides with an experimental value for the reactions of oxidation of Et2S. Additions of sodium metasilicate to accelerate of oxidation of Et2S by Н2О2 in water solutions. These data are consistent with a mechanism, including equilibrium formation of active peroxopolisilicate and its interaction with Et2S. The constant of stability of peroksopolisilicate (K=1,4 l/mol) and rate constant its reaction with Et2S (k = 0,15-0,3 l/mol с) were founded. Peroxopolisilicate in reactions with Et2S accordingly in 6 and 3 times more active than Н2О2 and МРВ, however approximately in 20 times lower than peroxocarbonate. The results are of importance for the development of new high-efficiency systems for desulphurization of liquid products of coking, recycling of sulfur-containing ecotoxicants (pesticides, toxic substances) and the search for new applications of the components of the cokechemistry fractions. Product Description popup.authors Анікєєва Н. М. Безбожна Т. В. Волкова Л. К. Жихарєв І.В. Зарайський А. П. Зубрицький М. Ю. Карпічев Є. А. Краснякова Т. В. Литвиненко С. Л. Мітченко С. А. Редько А. М. Рудаков Є. С. Фролова І. Б. Хазіпов О. В. Янатьєва Н. С. popup.nrat_date 2020-04-02 Close