Fructose to Sorbents: Synthesis of Metal-Organic Frameworks Directly from Biomass for Humid Shale Gas Separation

Abstract

The synthesis of metal-organic frameworks (MOFs) directly starting from biomass, making the most of renewable feedstocks and allowing for coupled or continuous processing, is intriguing. The interference of water (vapor) greatly hinders the wide utilization of MOFs in, e.g., recovering ethane from humid shale gas, which is a critical process for purifying natural gas in practical scenarios. Here, we propose a concept of direct ligand and MOF synthesis in a continuous routine, i.e., a linear synthesis of a bioderived ligand (furan-2,5-dicarboxylic acid), starting from a biomass source (fructose), followed by the in situ synthesis of a series of different MOFs. This strategy is also exempt from the tedious and energy-intensive processes of filtering, purifying, or drying intermediate products. The obtained renewable MOFs, particularly MIL-160(Al), reveal superior ethane capture abilities from shale gas mixtures under ambient conditions compared to most of the MOF materials reported to date. MIL-160(Al) also demonstrates a remarkable cycling nature and facile sorption regenerability to selectively capture ethane even under high-humidity conditions, as verified by static gas sorption measurement, experimental breakthrough tests, and in-depth theoretical studies, further conferring it with great potential for industrial applications.