FAN Guoce, TANG Congming, LI Xinli
(Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, China West Normal University, Nanchong 637009, China)
Abstract: An efficient catalyst composed of calcium pyrophosphate and calcium phosphate was developed to catalyze dehydration of lactic acid to acrylic acid. The catalyst compositions have a drastic influence on conversion of lactic acid and selectivity toward acrylic acid. When the catalyst composition in mass ratio of calcium phosphate to calcium pyrophosphate was changed from 30 : 70 to 50 : 50, higher conversion of lactic acid and higher selectivity toward acrylic acid were achieved. Other parameters such as reaction temperature, lactic acid concentration, liquid hourly space velocity, were also discussed. In addition, as one of the most important factors for heterogeneous catalysts, the stability of catalyst was checked. After running 56 hours, the conversion of lactic acid yet maintained above 96%, and the selectivity of acrylic acid also maintained above 57%. Characterizations of the catalysts were performed by XRD, TG, SEM, and FTIR.
Key words: dehydration; calcium phosphate; calcium pyrophosphate; lactic acid; acrylic acid
Journal of Molecular Catalysis, Vol. 26, Issue 6, 2012, 506-514