Screening of Low-Pressure Steam Heating Pretreatment Parameters For Enhanced Delignification of Pineapple Wastes

Abstract

Pineapple waste is classified as lignocellulosic biomass that can potentially be used in the production of biofuel (bioethanol) to replace the current resources of fossil fuels. Carbohydrate compositions of pineapple waste (cellulose and hemicellulose) are excellent properties to be exploited as fermentable sugars that can be converted into bioethanol through the fermentation process. In producing fermentable sugars from pineapple wastes, a pretreatment process is required to breakdown the complex crystalline structure of lignocellulose. However, this process is challenging due to the recalcitrant structure of lignocellulosic material. With this regard, extensive researches have been done to improve the efficiency of the pretreatment method for maximum removal of lignin from the lignocellulosic biomass. In this study, low-pressure steam heating pretreatment was introduced to examine the delignification effectiveness of pineapple wastes. In this study, screening of three parameters using low-pressure steam heating pretreatment (biomass loading, pressure, and residence time) were carried out using one-factor-at-a-time (OFAT) analysis. From the results obtained, the best condition for low-pressure steam heating pretreatment was found to be at biomass loading of 5 %w/v, 80 kPa pressure, and 30 minutes residence time. A total of 46.89 % lignin had successfully been removed from pineapple wastes by using this pretreatment condition. The proposed pretreatment in this present study was proven to be a practical approach for biomass delignification.