Precisely Patterned Nanostrand Surface of Cucurbituril[n]-Based Nanofiltration Membranes for Effective Alcohol-Water Condensation.

Low concentration alcohols produced by the state-of-art biological fermentation restrict the subsequent purification processes for chemical, pharmaceutical, biofuel and other applications. Herein, a rarely reported cucurbituril[n] (n=6, 8) is employed to pattern the thin-film composite membranes with controllable and quantifiable nanostrand structures through host-guest strategy. The resulting nanofiltration membrane with such morphology is the first report that exhibits excellent separation performance for isopropanol (IPA) and water, condensing initial 0.5 wt% IPA aqueous solution to 9.0 wt%. This not only provides a novel strategy for patterning nanostructural morphology, but also makes nanofiltration membranes promising for alcohol condensation in the biological fermentation industry that may reduce the energy consumption and post-processing costs.