Effect of instant controlled pressure drop pretreatment of lignocellulosic wastes on enzymatic saccharification and ethanol production

Abstract This work investigates the utilization of Eucalyptus chips and Aleppo pine cones as a feedstock for ethanol fuel production. Besides, we focus on the use of a new method for biomass pretreatment, namely instant controlled pressure drop (DIC). DIC treatment is a highly controlled process that combines steam pressure (up to 7 bar) with heat (up to 170 °C) during a short time. The end-product is a whole seed with a porous texture. A response surface methodology was used in order to evaluate the effects of processing parameters on the feedstock’s pretreatment efficacy and thus on the ethanol production. The response parameters were biomass’s moisture content before pretreatment, the cycle number and the total heating time. Saccharification yield (g reducing sugar/100 g pretreated biomass) is the response of this experimental design. The maximum saccharification yields obtained at optimal conditions for pretreated Eucalyptus chips and Aleppo pine cones were respectively 87% and 74% whereas the maximum ethanol yields were respectively 37.5 and 33.3 g of ethanol/100 g of sugars.