Organic Chemistry: Current Research
Open Access

Acid-base catalysis for valorization of glycerol and lactic acid

2^nd International Conference on Past and Present Research Systems of Green Chemistry

September 14-16, 2015 Orlando, USA

Bo-Qing Xu

Tsinghua University, China

Posters-Accepted Abstracts: Organic Chem Curr Res

Abstract :

Glycerol (GL) and lactic acid (LA) are two important bio-derivative platform moleucles, whose potential as renewable feedstock for energy and chemicals production have been the subject of many green chemistry research in recent years. This presentation intends to show the richness of chemicals prodcution from both GL and LA, featuring the key roles of heterogeneous catalysts for achieving high-selectivity towards specific prodcuts. Results from acid-base catalysis research in our laboratory are then presented to understand the requirement for surface acidity and basicity for the gas-phase GL dehydration to prodcue acrolein (AC) and the gas-phase LA dehydration to acrylic acid (AA). Catalytic evaluation under identical conditions of many solid catalysts with widely changed acid-base property demonstrates that the strongly acidic surface sites on the dry catalyst, with Hammett acidity function (H0) in �8.2 < H0 � �3.0, are most effective for offering high AC selectivity (� 60%) in the GL dehydration reaction but coexisting basic sites on the catalyst surface are detrimental to AC formation. On the other hand, the catalytic LA dehydration reaction data point to a mechanism of cooperative acid-base catalysis for the selective formation of AA. A ZSM-5 based catalyst is identified to show the up to date highest AA selectivity (ca. 80%) and yield (�70%), and longest catalytic durability (�80 h) in the LA dehydration reaction. Results from reaction kinetic studies will be presented to discuss the effects of reaction variables on reactant activation and product selectivity.

Biography :

Email: bqxu@mail.tsinghua.edu.cn