The catalytic conversion of lactic acid over various sodium salt catalysts and support materials has been carried out to identify potential catalyst/support combinations for 2,3-pentanedione and acrylic acid production. Low surface area, pure silica is the best support for suppressing undesirable side reactions to acetaldehyde and propanoic acid, which are favored over high surface area (microporous) or surface acidic materials. The best catalysts for 2,3-pentanedione and acrylic acid formation are the sodium salts of group IV and group V oxides, with sodium arsenate giving a 2,3-pentanedione yield of 25% and combined selectivity to acrylic acid and 2,3-pentanedione of 83% at 300 °C and 0.5 MPa total pressure.

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