Litteris et Artibus
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Item Synthesis of methacrylate monomers combined condensation of propionic acid and methylpropionate in the gas phase(Lviv Polytechnic Publishing House, 2016) Lapychak, Nazariy; Ivasiv, Volodymyr; Nebesnyi, Roman; Shatan, Anastasia-Bogdana; Lviv Polytechnic National UniversityDevelopment of active and selective catalyst for the process of obtaining methacrylate monomers from methyl propionate, propionic acid and formaldehyde is one of important stages to industrial implementation of this process. In order to solve this problem, we designed catalyst based on oxides of boron and phosphorus that were promoted by mixture oxides of zirconium and tungsten. The total yield of the target products at optimum temperature of 593 K is 52.3 % with the total selectivity of their formation at 96.4 % and the conversion of reagents of 54.2 %. We determined the effect of adding methanol on the ratio of products MMA/MAA.Item Synthesis, porous structure and catalytic properties of mixed vanadium-titanium phosphates in aldol condensation reaction of acetic acid with formaldehyde(Lviv Polytechnic Publishing House, 2016) Nebesnyi, Roman; Shpyrka, Iryna; Sydorchuk, Volodymyr; Khalameida, Svitlana; Khalameida, Svitlana; Ivasiv, Volodymyr; Orobchuk, Oksana; Zavalii, Kateryna; Lapychak, Nazariy; Lviv Polytechnic National University; Institute for Sorption and Problems of Endoecology of NAS of UkraineMixed vanadium-titanium phosphates as well as individual vanadium and titanium phosphates were prepared via precipitation from sulfate aqueous solutions. Co-precipitated phosphates were modified through mechanochemical treatment (MChT) and characterized using the adsorption-structural methods. The aldol condensation of acetic acid with formaldehyde to acrylic acid has been used as a test reaction. Reduction of optimum reaction temperature from 623 K to 573 K on the treated catalysts is observed.Item Catalysts of aldol condensation of acetic acid with formaldehyde(Видавництво Львівської політехніки, 2017-12-23) Shpyrka, Iryna; Nebesnyi, Roman; Sydorchuk, Volodymyr; Khalameida, Svitlana; Ivasiv, Volodymyr; Zavalii, Kateryna; Lviv Polytechnic National University; Institute for Sorption and Problems of Endoecology of NAS of UkraineIt had been demonstrated that mechanochemical and hydrothermal treatment of support allows increasing activity and selectivity of the catalyst in the studied process. Hydrothermal treatment (HTT) of silica increases mechanical strength of silica gel granules subjected to hydrothermal treatment, also reduction of coke formation takes place, as well as prolongation of the catalysts life. Similarly, the same approaches allow to optimize the pore structure of titanium phosphates.Item Single stage acrylic acid obtaining based on methanol and acetic acid(Lviv Polytechnic Publishing House, 2015) Nebesnyi, Roman; Shpyrka, Iryna; Shatan, Anastasiia-Bohdana; Lukiyanchuk, Andriy; Ivasiv, Volodymyr; Nebesna, Yuliia; Lapychak, Nazariy; Lviv Polytechnic National UniversityThe new complex oxide acid type catalysts were developed and their performance in the process of aldol condensation of acetic acid with formaldehyde to acrylic acid was studied. The optimum conditions of the process were determined. It was established that these catalysts are effective in the process of methanol to formaldehyde oxidation, and also in the process of single stage acrylic acid obtaining from acetic acid and methanol in the presence of air.Item Simultaneous methyl methacrylate and methacrylic acid obtaining over zirconium-containing catalysts(Lviv Polytechnic Publishing House, 2015) Nebesna, Yuliia; Nebesnyi, Roman; Ivasiv, Volodymyr; Lapychak, Nazarii; Lviv Polytechnic National UniversityMethyl methacrylate and methacrylic acid are widely used monomers. The aldol condensation of methyl propionate and formaldehyde is perspective process for simultaneous obtaining of this methacrylate monomers. It was found that zirconium-containing catalysts are active in this process. The effect of zirconium content in the catalyst on methyl propionate conversion and yield of methyl methacrylate and methacrylic acid has been determined. The best catalyst for methyl propionate condensation with formaldehyde has been found.