Acrylic acid synthesis from lactic acid over hydroxyapatite catalysts with various cations and anions

作者：Matsuura Yumiko; Onda Ayumu^*; Ogo Shuhei; Yanagisawa Kazumichi

来源：Catalysis Today, 2014, 226: 192-197.

DOI：10.1016/j.cattod.2013.10.031

• Hydroxyapatite
• Acrylic acid
• Lactic acid
• Acid-base properties

We prepared substituted hydroxyapatite catalysts, such as Ca-10(PO4)(6)(OH)(2), Sr-10(PO4)(6)(OH)(2), Pb-10(PO4)(6)(OH)(2), Ca-10(VO4)(6)(OH)(2), and Sr-10(VO4)(6)(OH)(2), and carried out conversions of lactic acid over the prepared catalysts. The hydroxyapatite catalysts had stabilities for the reaction media under flowing gas including lactic acid and water at 623 K. The hydroxyapatite catalysts exhibited markedly higher acrylic acid yields than those of P2O5/SiO2 and MgO catalysts. In the lactic acid conversions, the relatively acidic catalysts, such as P2O5/SiO2, Ca-10(VO4)(6)(OH)(2) and Sr-10(VO4)(6)(OH)(2) catalysts, accelerated the formations of acetaldehyde and propionic acid, whereas the relatively basic catalysts, such as MgO and Pb-10(PO4)(6)(OH)(2) catalysts, gave large amounts of unidentified products. On the other hand, the moderate acid-base catalysts, such as Ca-10(PO4)(6)(OH)(2) and Sr-10(PO4)(6)(OH)(2) catalysts, selectively accelerated the dehydration of lactic acid into acrylic acid.

• 出版日期2014-5-1