Techno-Economic Evaluation to Reduce the Costs Associated with Copper-Catalyzed Alkaline Hydrogen Peroxide (Cu-AHP) Pretreatment of Hardwoods

Pretreatment costs are one of the primary barriers to establishing a fully commercialized cellulosic ethanol industry. Overall, cost considerations for an individual pretreatment process will vary depending on a multitude of variables including, but not limited to, feedstock availability, pretreatment chemistry, capital equipment, co-product generation, and product recovery. Heretofore, copper-catalyzed alkaline hydrogen peroxide (Cu-AHP) pretreatment has shown to be quite useful in obtaining both hexose and pentose sugar yields in excess of 90%. In an attempt to understand the factors that can enhance or limit this process on an industrial scale, a techno-economic analysis was performed around the pretreatment and biochemical conversion process. The primary drawback associated with the Cu-AHP pretreatment are the initial chemical costs associated with the high price of the 2,2’-bipyridine ligand and hydrogen peroxide. Although chemical loadings have been decreased while still achieving very high sugar yields, the techno-economic analysis is necessary to realize a more practical way to implement the pretreatment as a viable commercial process. Furthermore, this analysis yielded favorable insight into process synthesis, particle size reduction of biomass, and chemical recovery to offset increased production costs. Finally, a minimum ethanol selling price (MESP) was calculated and compared to other leading pretreatment strategies to assess the process viability of Cu-AHP pretreatment.