New catalysts B–P–V–W–Ox/SiO2 of gas-phase condensation of acetic acid from formaldehyde to acrylic acid on an industrial carrier of stable chemical composition (colloidal silicon oxide, Aerosil A-200) were synthesized. It is shown that the hydrothermal treatment of the carrier allows to increase the activity and selectivity of the catalyst in the reactions of aldol condensation of acetic acid with formaldehyde.
Due to the low efficiency of known catalysts of aldol condensation of acetic acid with formaldehyde, studies aimed at creating new or improving existing catalysts of this process are relevant. Creation of active and selective condensation catalysts will facilitate the industrial introduction of acrylic acid production by means of aldol condensation.
The process of aldol condensation of acetic acid with formaldehyde in the presence of solid oxide catalysts in gas phase has been investigated. The optimum content of active components in the catalyst and the optimum content of promoter in the catalyst for the process of acrylic acid obtaining has been determined. Досліджено процес альдольної конденсації оцтової кислоти з формальдегідом у присутності твердих оксидних каталізаторах у газовій фазі.
The process of acrylic acid obtaining by gas-phase condensation of acetic acid with formaldehyde over fumed silica based catalysts has been investigated. The effect of catalyst treatment method on its catalytic properties has been determined. The optimal catalyst for acrylic acid obtaining has been defined.
The basic kinetic regularities of aldol condensation reaction of propionic acid with formaldehyde on the B2O3-P2O5-WO3/SiO2 catalyst in gas phase have been investigated. The kinetic equations of the process have been proposed and the kinetic parameters have been calculated. The created kinetic model fairly well describes the condensation reaction of propionic acid with formaldehyde on the developed catalyst.