Highly Selective Production of Acrylic Acid from Glycerol via Two Steps Using Au/CeO₂ Catalysts

Using biomass resources for chemical production can provide more sustainable development in the chemical industry. In this work, acrylic acid was selectively produced from glycerol via two steps: Glycerol was efficiently converted to allyl alcohol by formic acid-mediated deoxydehydration (DODH), and then, the obtained allyl alcohol was oxidized without purification into acrylic acid in a basic aqueous solution. The Au/CeO2 catalysts were used for the selective oxidation, and it worked well even in the presence of residual formic acid and impurities. A high yield of 87% was obtained for the production of acrylic acid from glycerol: 94.5% from glycerol to allyl alcohol and 92% from allyl alcohol to acrylic acid. The different shapes of CeO2 such as rods, octahedra, and cubes were used as supports to deposit the Au active phase. Au deposited on octahedral CeO2 presented the highest yield toward acrylic acid, and it was the most stable for the repeated oxidations. The effects of reaction time, temperature, O2 pressure, and allyl alcohol concentration were evaluated to maximize the yield toward acrylic acid.