Batch and continuous esterification for the direct synthesis of high qualified biodiesel from waste cooking oils (WCO) with Amberlyst-15/Poly (vinyl alcohol) membrane as a bifunctional catalyst

Abstract Biodiesel, a mixture of fatty acids alkyl esters (FAAE), has recently received great concern as an excellent alternative to the petro-based diesel fuel. However, the production of biodiesel at commercial scale is obstructed by both cost of feedstock and the homogeneous catalyst system. To overcome these challenges, Amberlyst-15 /Poly (vinyl alcohol) membrane (A-15/PVA) with catalytic and water-adsorbing dual functions have been prepared by a simple phase inversion method. The as-prepared A-15/PVA exhibited excellent catalytic activity and reusability in both batch and continuous esterification of acidified oil from waste cooking oil (WCO) with methanol for biodiesel production. The produced biodiesel exhibited high qualified properties and stability and can be directly applied in current diesel engines without modifying the engines. The exhaust of the biodiesel and biodiesel-blend could decrease the smoke opacity, carbon monoxide, hydrocarbon, while increase the nitrogen oxide emissions. The A-15/PVA demonstrated great potential in industrial production of biodiesel with high qualities from WCO.