A New Generation of Zirconia Supported Metal Oxide Catalysts for Converting Low Grade Renewable Feedstocks to Biodiesel

A new class of zirconia supported metal oxide catalysts has demonstrated the ability to convert low quality bio-oils, high in FFA, to biodiesel. Operating at mild to moderate reaction conditions, 195°C and 300psi, these catalysts can perform simultaneous esterification and transesterification reactions to achieve FAME yields as high as 90% in a single reaction step. This suggests that a wide range of crude bio-oil feedstocks, with varying FFA content, including palm oil (FFA 12%), residual corn oil(15%) from the distiller dried grains (DDGs), animal fats (2~35%), yellow grease (<15%), and brown grease (50~100%), can be converted into FAME with this catalyst technology. The heterogeneous nature of the ZrO₂ formulations also simplifies the production process while avoiding the problems inherent in homogeneous processes related to separation and washing, corrosive catalyst, and excessive methanol usage.