Economic assessment and life cycle analysis of sugarcane bagasse valorization to bioethanol via one‐pot deep eutectic solvent pretreatment

The increasing global demand for sustainable fuels has heightened interest in lignocellulosic biomass conversion to ethanol. This study presents a technoeconomic and life cycle assessment (LCA) of novel one‐pot ethanol production from sugarcane bagasse using microwave‐assisted ternary deep eutectic solvent (DES) (choline chloride:ethylene glycol:nickel chloride hexahydrate in a molar ratio of 1:2:0.016) pretreatment. The process included microwave‐assisted DES pretreatment, enzyme hydrolysis and fermentation in a one‐pot multistep approach, followed by downstream separation and purification. A combination of process modeling from experimental data and Aspen Plus simulation for downstream separation was applied to the analysis of a plant with a capacity to produce 100 t of ethanol per day. The plant was assumed to be annexed to a sugar mill. OpenLCA 2.0 was used to construct the LCA model to analyze and quantify the environmental impact associated with producing 1 kg of ethanol as the functional unit. Further, to increase the robustness and reliability of the process, different scenarios and sensitivity analyses were studied. The base case considered was 10% solid loading at pretreatment and no recycling of pretreatment solvent, which resulted in a production cost of 1098 USD per t with a payback period of 5 years. The sensitivity analysis identified process improvement opportunities where increasing solid loading and DES loading could significantly reduce production cost by 30% and global warming potential, by 91%. Economic assessment revealed that increasing plant capacity would significantly reduce the production cost per t of ethanol, highlighting the benefits of scaleup in improving financial viability. These results underscore the value of integrated process optimization in enhancing bioethanol production while mitigating the associated environmental burden.