Research Into Epoxidation Process of the С9 Fraction Hydrocarbons and Unsaturated Co-oligomers by Peroxyethanoic Acid

We have studied regularities of the epoxidation process of the С9 fraction of liquid by-products of the pyrolysis of hydrocarbons and co-oligomers based on the С9 fraction with peracetic acid. It is established that the use of the specified system makes it possible to achieve high values of conversion for double bonds and the selectivity of epoxidation process, sufficiently high yield of epoxy-containing co-oligomers. We established the possibility to use the С9 fraction of liquid by-products of hydrocarbon pyrolysis (the accompanying product of ethylene production) as a raw material for obtaining epoxides, which is a rational method in order to dispose of the fraction. We analyzed experimental dependences of reagents consumption and the formation of epoxide in the reaction of the С9 fraction epoxidation. It was established that the resulting values for selectivities of the epoxidation process by double bonds when obtaining epoxy-containing co-oligomers are the highest in the case of epoxidation of co-oligomers, synthesized by the heterogeneous catalytic co-oligomerization of the С9 fraction S9 hydrocarbons using, as a catalyst, activated bentonite clay. The synthesized epoxy-containing co-oligomers retain residual unsaturation. It is obvious that the unsaturated bonds of styrene, vinyl toluene, α-methyl styrene, allylbenzene links at the ends of a co-oligomer macromolecules are easily epoxidized. The selectivity of epoxidation of co-oligomers, obtained by different methods of co-oligomerization of the С9 fraction hydrocarbons (homogeneous catalytic, heterogeneous catalytic, initiated, and thermal) is different (60.2‒96.1 %) and depends on the nature of the starting co-oligomer. Using the methods of 1H NMR-, Raman-, and infrared spectroscopy, we confirmed the high content of epoxy groups in the composition of epoxy-containing co-oligomers and the progress of the epoxidation reaction. Applying the method of 1H NMR spectroscopy, we established the presence of epoxy groups formed based on the resulting vinyl double bonds of co-oligomers. Due to the content of oxirane oxygen and a high reaction ability of the oxirane ring, epoxy-containing co-oligomers can act as the raw material for subsequent obtaining of various chemical substances: glycols, carbonyl compounds, plasticizers, polymers

Heterogeneous catalytic oligomerization of olefin-containing fractions of hydrocarbons pyrolysis liquid products as a reasonable way of their utilization

The work is devoted to the obtaining of co-oligomers from the byproducts of ethylene production. The above products were obtained using heterogeneous acidic catalysts having the nature of silica-alumina. The specific surface area of the catalysts was defined by methylene blue adsorption method. The yields and properties of the products obtained in the presence of various catalysts were analyzed. The relationship between the structure of the catalyst and its effectiveness in the co-oligomerization process was analyzed

Examining the Epoxidation Process of Soybean Oil by Peracetic Acid

The main principle of green chemistry is the use of renewable, ecological raw materials, which will contribute to subsequent biodegradation and reduction of toxicity of the product in the production of polymers. Vegetable oil (VO) is the cheapest and most common biological raw material, the use of which has such advantages as low toxicity and natural biodegradation.We analyzed experimental dependences of the consumption of reagents and the accumulation of epoxide in the interaction between a solution of soybean oil (SO) in toluene and the epoxidizing systems H2O2/acetic acid (AA)/KU-2´8 and H2O2/acetic anhydride (AAn)/KU-2´8.It was established that the use in the process of epoxidation of soybean oil of the specified systems makes it possible to achieve high values of selectivity of epoxidation by double bonds. The resulting values of selectivities in the epoxidation process by double bonds and by the consumption of peroxide when studying the epoxidizing system Н2О2/AAn/KU-2´8 are higher. The advantages of using the specified epoxidizing system include a reduction in the total volume and mass of the reaction mixture. Obtaining the epoxidized soybean oil with a low resulting value of bromine number provides subsequent good thermal and oxidative stability of materials on its base.We calculated the values of rate constants of the epoxidation reaction of SO at different temperatures. By using the methods of IR and Raman spectroscopic studies, we demonstrated structural changes in raw materials and confirmed the progress of the epoxidation reaction. The developed technique for recalculating the values of bromine, iodine numbers of products of the epoxidation reaction, unsaturation and epoxy number, selectivity of the process in the epoxidation of mixtures of unsaturated compounds allows comparing the results of research. The use of the specified technique also makes it possible to draw unambiguous comparative conclusions about the effectiveness of reagents consumption and the selectivity of reaction. In this case, there is a possibility to improve the technology of obtaining the epoxidized compounds. The calculation formulas obtained were applied to analyze the progress of the epoxidation process of soybean oil

Research Into Esterification of Mixture of Lower Dicarboxylic Acids by 2-ethylhexan-1-ol in the Presence of P-toluensulfonic Acid

Regularities of esterification of the mixture of lower dicarboxylic acids (succinic, glutaric, adipic) by 2-ethylhexan-1-ol in the presence of catalysts – p-toluensulfonic and sulfuric acids under non-stationary conditions were studied. It was found that in the presence of mineral acid, the reaction flows at a lower rate. Application of benzene as a substance that facilitates separation of water, formed in the esterification reaction, makes it possible, due to a lower reaction temperature, to decrease energy consumption of the process at an increase in conversion of dicarboxylic acids from 95.8 to 99.5 %. It was shown that the use of activated carbon of different brands simultaneously with catalysis by p-toluensulfonic acid with virtually the same effectiveness can decrease chromaticity intensity of esterification products by more than three times. The use of finely dispersed activated carbon 208CP and DCL 200 compared with coarse-grained activated carbon BAU-A additionally provides higher intensity of esterification reaction due to improvement of removal of water from the reaction mixture. It was found that an increase in the content of activated carbon DLC 200 by more than 0.3 % by weight in the reaction mixture contributes to a sharp decrease in the process intensity. This influence is explained by neutralization of a part of the catalysts by alkaline components of activated carbon, which decreases its active concentration and inhibits the reaction. Optimum conditions of the esterification process were proposed. The authors determined dependences of density and kinematic viscosity of the mixture of diesters of succinic, glutaric and adipic acids, and 2-ethylhexan-1-ol, separated from the esterification reaction products, on temperature and described them with regression equation