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Systematic studies of acrolein oxidation and oxidative alkoxylation catalyzed by Se-modified microgel catalysts under mild reaction conditions were conducted. Se-modified microgels proved to be highly active colloidal catalysts and exhibited high performance for the oxidation of acrolein to acrylic acid and oxidative alkoxylation to the corresponding methyl/ethyl/butyl acrylates using hydrogen peroxide as a green oxidant. Methyl acrylate or acrylic acid can be synthesized in high yield (89-91%) and with high selectivity (97-99%) simply by regulating the solvent type and the concentration of selenium moieties in the microgel structure. Se-microgels exhibit exceptional catalytic activity compared with other Se-containing molecules of organic and inorganic nature. Due to the unique properties of the microgels that combine advantages from homogeneous and heterogeneous catalytic systems in terms of activity and selectivity as well as re-use possibilities, Se-microgel catalysts can be easily separated and reused in several catalytic cycles and remain highly active.

The influence of mechanochemical treatment of catalysts on the process of aldol condensation of acetic acid with formaldehyde into acrylic acid in the gas phase was investigated. The active phase components B2O3–P2O5–WO3–V2O5/SiO2 of the catalyst studied during the mechanochemical treatment of the carrier (silica gel of the KSKG brand) and the wet gel SiO2 in the aqueous solution, which was performed in term to determine the influence of catalysts porous structure modification on the catalytic properties of the catalyst. Mechanochemical treatment was performed at 300 rpm, 500 rpm, 650 rpm and 800 rpm. The atomic ratio of components in catalyst B:P:W:V is 3:1:0.18:0,12. The catalytic properties of the obtained catalysts were investigated in the reaction of aldol condensation of acetic acid with formaldehyde at the temperature range from 573 to 673 K, the contact time of 8 s with the equimolar ratio of the initial reagents. The influence of the reaction temperature and the conditions of the mechanochemical treatment of the catalyst on the parameters of the condensation process of acetic acid with formaldehyde was established. The best of the investigations is a catalyst subjected to mechanochemical treatment in water at 300 rpm. The optimal conditions for the process are temperature 648 K, contact time 8 s. Under these conditions, it was possible to achieve the acrylic acid yield of 65,8 % with 91,3 % selectivity and 72,1 % of acetic acid conversion, which is better than that of a not treated catalyst (the yield of acrylic acid is 57 %, with a selectivity of 89 % and a conversion of 64,1 %). The comparison of the catalytic activity of the previously developed crude catalyst based on the silica gel of the KSKG; a carrier which was subjected to hydrothermal treatment at 150 °C, a catalyst with mechanochemical treatment of the carrier at 300 rpm and a catalyst with a mecha

In this work comparative overview of the main promising methods of acrylic acid production is performed. Due to availability of the raw materials, base the development of acrylic acid production methods from glycerine (by-product of biodiesel production), as well as by fermentation of biomass, has become significant. In addition, it is shown that the improvement of the catalysts for aldol condensation of acetic acid with formaldehyde into acrylic acid makes this method of acrylic acid synthesis one of the most competitive. It is established that modification of B–P–W–V–Ox/SiO2 catalysts porous structure for the process of aldol condensation is an effective way of influencing their catalytic properties. Increasing of catalysts performance is mostly associated with changing of pore size distribution of the catalysts surface. In addition to increase of mechanical strength of silica gel granules subjected to hydrothermal treatment, reduction of coke formation takes place. The optimal pore size of B–P–W–V–Ox/SiO2 catalysts is 11-16 nm. Such porous structure is achieved after hydrothermal treatment of silica support at the temperature range 125-175 °C for 3 h. Under optimal reaction conditions (temperature 380 °C, contact time 8 s) the yield of acrylic acid in the process of aldol condensation of acetic acid with formaldehyde is 68 % with 91 % selectivity of its formation. Created catalysts are also efficient in oxidative condensation process (oxidative condensation of methanol with acetic acid to acrylic acid and methylacrylate). The feature of this process is simultaneous obtaining of two valuable monomers – acrylic acid and methylacrylate. The total yield of acrylates is 54.7 % with 80.1 % selectivity of their formation (temperature 400 °C, contact time 8 s). The paper also shows the prospects for using the newest Se-containing catalytic systems on a microgel basis for low-temperature synthesis of acrylic acid

The purpose of the work was to determine the influence of different mesoporous carriers: SiO2, TiO2 anatase of TiO (OH), ZrO2, SnO2-TiO2, Al2O3 on their efficiency in the process of aldol condensation of acetic acid with formaldehyde with the formation of acrilyc acid. To achieve this goal, the following tasks must be solved. Firstly, it is necessary to investigate the ability of the developed catalyst to intensify the process of acrylic acid production and to determine the optimal parameters of the process. Secondly, we should establish dependence of selectivity, yield of acrylic acid and conversion of reagents from temperature. The catalysts were prepared by impregnating the carrier with a saturated solution of the active phase components. The atomic ratio of components in catalyst B:P:(W+V) is 3:1:0.3; atomic ratio is W:V=2:3. The catalytic properties of the obtained catalysts were investigated in the reaction of aldol condensation of acetic acid with formaldehyde at the temperature range from 573 to 673 K, the contact time of 8 s with the equimolar ratio of the initial reagents. B – P–W – V–Ox catalysts that were applied on SiO2, TiO2 anatase of TiO(OH), ZrO2, SnO2-TiO2 and Al2O3 carriers with a size of pore about 10 nm showed high efficiency. At the same time, the yield of the product as well as the selectivity of its formation were different when various different carriers were used, indicating the influence of carrier nature on the catalytic properties of the carrier. The effect of the process conditions (temperature and contact time) on the parameters of condensation of acetic acid with formaldehyde has been determined. The optimum temperature for carrying out the process is 648 K and a contact time – 8 seconds. Under these conditions it was possible to achieve 49 % acrylic acid yield with a selectivity of 94 % and conversion of acetic acid 52 % using catalyst TiO2 anat