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

A one‐step aldol condensation reaction of methyl propionate and formaldehyde to produce methyl methacrylate is a promising environmentally sustainable strategy. In this work, the aldol condensation reaction was firstly conducted in a fluidized bed reactor using different types of catalysts. Zirconium and cesium‐loaded SiO 2 and Al 2 O 3 acid‐base bifunctional catalysts were prepared by wetness impregnation. Experimental results demonstrated the 15 % Cs‐0.05 %Zr/SiO 2 (100–200 mesh) catalyst exhibited excellent catalytic performance. The effects of the supports, reaction temperature, carrier gas flow rate, and feed rate were investigated and optimized. When the flow rate of carrier gas (N 2 ) was 280 cm 3 /min and the feed rate was 0.6 cm 3 /min, the methyl propionate conversion was 25.2 % and the methyl methacrylate selectivity could reach 86.1 %. Although the catalytic activity of the 15 %Cs‐0.05 %Zr/SiO 2 catalyst dropped with reaction time on stream due to carbon deposition on the surface of catalyst, its activity was restored by a simple regeneration method.