(43b) Evaluating Endocarp Biomass As Potential Feedstocks for Biorefinery

Lignin is an aromatic biopolymer that provides structural support to plant cell walls. Lignin is highly abundant and serves as a potential feedstock for the production of biofuels and value-added chemicals and materials. Drupe endocarp biomass such as peach pits, walnut and almond shells, display the highest lignin content of biomass sources. These endocarp biomass arise as agricultural waste that are non-edible and cannot be re-integrated into the soil. Its high bulk and energy density makes it a preferable feedstock for biorefineries to produce high yield and increased value. In this study, we characterized the compositional, structural and mechanical properties of different sources of endocarp biomass and explored the feasibility of its utilization as a feedstock for bioproducts. First, we conducted a compositional analysis of walnut and peach endocarps to determine lignin content. Then their structural properties were examined using imaging from scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). We also used a texture analyzer machine to perform a texture analysis in order to evaluate the contribution of lignin content to its mechanical properties and determine the force and energy input required in processing the endocarps. Based on the experimental data, a cost and economic analysis was conducted on the logistics, distribution and processing of drupe endocarps as a feedstock for biorefineries. Overall, utilization of high lignin content endocarps as feedstock will not only provide a sustainable solution to agricultural waste but also improve efficiency and yield for the production of renewable energy sources and value-added products.