Effects of Ultrasonic Vibration-Assisted Pelleting on Sugar Yield in Biofuel Manufacturing With Different Pretreatment Methods

There are many concerns taking place due to the reliability and sustainability of petroleum-based liquid transportation fuels. The importance of finding an alternative fuel source to the petroleum-based fuels is in high demand. One promising alternative is cellulosic biofuels that offer numerous benefits for the environment. However, there are some obstacles in the way of manufacturing the cellulosic biofuels at a large scale and doing so cost effectively. One obstacle is the low sugar yield of biomass in enzymatic hydrolysis, leading to low efficiency in biomass-biofuel conversion and thus high conversion costs. Pretreatment of biomass is required to achieve high sugar yield in enzymatic hydrolysis. Dilute acid pretreatment and hot water pretreatment can effectively increase the sugar yield, but they usually involve high temperature or excessive use of acid, making pretreatment one of the most costly process in cellulosic biofuel manufacturing. This study investigated effects of ultrasonic vibration-assisted pelleting on the sugar yield of biomass pretreated by the two pretreatment methods. Results showed that, for both pretreatment methods, pellets produces higher sugar yield than particles. Furthermore, at the same pretreatment temperature, the water-pretreated pellets produced higher sugar yield than acid-pretreated particles.