Aldol condensation of acetic acid with formaldehyde to acrylic acid over Cs(Ce, Nd) VPO/SiO₂ catalyst

Abstract

The Cs-, Ce-, and Nd-modified VPO/SiO2 exhibited higher activity for aldol condensation of acetic acid with formaldehyde to acrylic acid.

Acrylic acid synthesis via condensation of acetic acid and formaldehyde catalyzed by silica aerogel‐supported SiW/PW/PMo oxides

“…Various catalysts have been employed in the aldol condensation reaction of acetic acid and formaldehyde, such as acids, bases and base–acid bifunctional catalysts, among which acid–base bifunctional catalysts attract most attention owing to the cooperation between acid and base active sites. The acidic sites, especially the weak ones, are essential to trigger the aldol condensation reaction, and the high acid amount is favorable for formaldehyde conversion.…”

“…In our previous work, V‐P‐O catalysts were prepared with various supports, and doped with a variety of alkali metals. It was found that high acid and alkali quantities led to high catalytic activities for the aldol condensation of acetic acid with formaldehyde to acrylic acid …”

Gaseous catalytic condensation reaction of methyl propionate and formaldehyde in a fluidized bed reactor

“…The main issue of this reaction is the low yield of MMA and the poor stability of the catalyst. Acidic catalysts, basic catalysts, and acid‐base bifunctional catalysts all catalyze the reaction . The V‐Si‐P ternary oxide catalysts were prepared and the catalytic performances in the reaction of MP and methylal to produce MMA were investigated by Ai .…”

Reaction between methanol and acetic acid catalyzed by SiO2‐supported V‐P‐O catalyst in oxygen atmosphere

“…Acetic acid is commercially produced on a large scale and begins with methanol and CO. Formaldehyde is produced as a by‐product in many chemical processes. A significant amount of research has been conducted on the synthesis of acrylic acid (or methyl acrylate) via the aldol condensation reaction of acetic acid (or methyl acetate) with formaldehyde catalyzed by alkaline metals and V‐P‐O oxides . When the Cs/SBA‐15 catalyzed the aldol condensation reaction between the methyl acetate and the formaldehyde, the methyl acrylate selectivity was able to reach 95 % at a methyl acetate conversion of 48.4 % .…”

“…It was proposed that the β‐VOPO 4 , δ‐VOPO 4 , and distorted (VO) 2 P 2 O 7 phases played important roles in the formation of acrylic acid and methyl acrylate . The addition of alkaline metals in the V‐P‐O oxide catalysts caused the formation of phosphate salts and changed their alkaline and acidic properties, subsequently improving their catalytic performance in the formation of acrylic acid …”