(496a) Recent Advances in Intensification of Bio-Based Processes By Ultrasound and Hydrodynamic Cavitation

Over the last two decades, there has been a plethora of studies utilizing ultrasonic and hydrodynamic cavitation to intensify and optimize the homogeneous and catalytic synthesis of biodiesel and the conversion of lignocellulosic biomass to ethanol and other chemicals for biofuels production so as to reduce cost and make the processes economically attractive for large-scale production. Cavitation is the formation, growth and implosive collapse of gas- or vapor-filled microbubbles and can be induced acoustically or hydrodynamically in a body of liquid. Cavitation is known to produce extreme conditions of temperatures and pressures. The cavitation event also gives rise to acoustic microstreaming or formation of miniature eddies that enhance the mass and heat transfer in the liquid. Biodiesel has become one of the premier forms of alternative energy source. Biodiesel is produced by the reaction of lipid feedstocks with an alcohol such as methanol in the presence of homogeneous catalysts as NaOH, KOH or their methoxides, and acids such as H₂SO₄, H₃PO₄; and solid superacid catalysts. The conversion of lignocellulosic biomass for biofuels and biorefinery applications is also limited due to the cost of pretreatment to separate or access the biomass’s three main components, cellulose, hemicelluloses, and lignin. Ultrasound and/or cavitation-assisted technologies are green techniques that have the potential to enhance the separation and hydrolysis of lignocellulosic materials for the use in biofuel production and biorefineries, through physical and/or chemical mechanisms. This talk will discuss the role of catalysis and ultrasound-assisted processes in energy sustainability, and economic challenges in the development of green routes for bio-energy and bio-refineries. A synopsis of the some results of our on cavitation-enhanced intensification and optimization of the syntheses of biofuels from edible and non-edible biomass will also be presented.