aldol condensation

Mixed 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.

it 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

Methyl 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.

The 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.