Metal–organic framework ZIF-8 nanocomposite membrane for efficient recovery of furfural via pervaporation and vapor permeation

Furfural (2-furancarboxaldehyde) has been regarded as an important platform molecule in biorefinery and has gain a wide range of applications. With the state-of-the-art biorefinery technique, the concentration of furfural in the product water stream is generally low (around 3 wt%). It is therefore highly desirable to develop efficient alternative recovery technologies that can lower the recovery costs, thus improving the economics of furfural production. In this work, a homogeneous ZIF-8-silicone rubber nanocomposite membrane with high particle loading was successfully fabricated on a hierarchically ordered stainless-steel-mesh (HOSSM) employing a novel “Plugging–Filling” method. The membrane exhibits the highest pervaporation separation index (separation factor 53.3 and total flux 0.90 kg m−2 h−1) reported so far and excellent stability in a test of more than 120 h at 80 °C for recovery of furfural (1.0 wt%) from water. This very high performance should be attributed to the exceptional adsorption selectivity and capacity of ZIF-8 toward furfural molecules and the effects of space restriction and physical cross-linking of the HOSSM. This is a good demonstration of the potential of MOF membranes for separating biomass derived compounds in biorefinery processes.