(54e) Technoeconomic Assessment of Biofuel and Biochemical Production Using New Pretreatment Processes for Lignocellulosic Biomass and Lignin Valorization

Fasahati, P., University of Wisconsin-Madison
Saffron, C. M., Michigan State University
Recently developed extractive ammonia (EA) and copper–bipyridine catalyzed alkaline hydrogen peroxide (AHP) pretreatments are capable of solubilizing a large portion of lignin in lignocellulosic biomass. Liquefied lignin can be valorized through electrochemical processes to produce value-added biochemicals such as cyclohexanol which is a Nylon 6,6 precursor. In addition, lignin removal improves saccharification by increasing the carbohydrate accessibility to the enzymes. This study evaluates the potential of two pretreatment processes for bioethanol and biochemical production from lignocellulosic biomass, namely: 1) extractive ammonia (EA) pretreatment and 2) copper–bipyridine catalyzed alkaline hydrogen peroxide (AHP) pretreatment. Both processes are simulated in Aspen Plus v8.8 to obtain heat and material balances required for energy and economic assessments. Technoeconomic models are developed to calculate the minimum ethanol selling price considering a 10% internal rate of return and 30 years of plant life. Results showed that high ammonia-to-biomass ratio in EA makes the ammonia recovery highly energy intensive. Similarly, high hydrogen peroxide and bipyridine demand in AHP makes it a costly process. Therefore, reducing the amount of pretreatment chemicals is required to improve the economic viability of both processes. Finally, sensitivity analyses on different process parameters were performed to identify the pitfalls and potential of each process for further development and economic profitability.