(570e) Separation and Purification of 2,5-Dimethylfuran: Process Design and Comparative TEA and Sustainability Evaluation of Advanced Adsorption and Conventional Distillation

The furanic chemical 2,5-dimethylfuran (DMF) is an attractive biobased fuel and feedstock. High-yield biphasic processes for DMF synthesis from sugars employ higher alcohols such as n-butanol (BuOH) as solvents. This leads to a product containing < 8 wt% DMF and byproducts in BuOH solvent along with water. DMF process economics is strongly influenced by separation costs for DMF purification and recycle of BuOH and water. We previously demonstrated efficient adsorptive separation of DMF with a stable ZIF-8 metal-organic framework adsorbent [1]. Here we present a detailed, comparative technoeconomic analysis and sustainability evaluation of adsorptive versus conventional distillation separation processes to produce 98 wt% pure DMF at 100 metric tons/day. The novel adsorptive process integrates a simulated moving bed (SMB) unit with water removal and desorbent recovery systems, whereas the distillation process relies on multiple columns operating at different pressures to handle the strongly non-ideal multicomponent thermodynamics. Rigorous process modeling is conducted by a combination of the Aspen Plus flowsheet simulation package and our in-house SMB modeling and optimization package written in AMPL, with realistic multicomponent adsorption and vapor-liquid equilibrium models parametrized by experimental data. This is followed by detailed calculations and sensitivity analysis of bare-module, utility, and material costs. The net present values (NPVs) of the process alternatives show a clear long-term economic advantage of the adsorptive process, mainly due to large reduction in utility costs. When translated to a large potential DMF biofuel market size similar to that of bioethanol, the SMB-based adsorptive process would save >$8B/yr globally in separation costs. Furthermore, calculation of energy and CO₂ sustainability indices shows very clear advantages of the adsorption process.

References:

[1] Y. Chiang, W. Liang, S. Yang, C. R. Bond, W. You, R. P. Lively, S. Nair, Separation and Purification of Furans from n-Butanol by Zeolitic Imidazole Frameworks: Multicomponent Adsorption Behavior and Simulated Moving Bed Process Design, ACS Sustainable Chemistry & Engineering 7 (19), 16560-16568 (2019)