A biodegradable composite filter made from electrospun zein fibers underlaid on the cellulose paper towel

Conventional petroleum-based synthetic polymeric fiber filter materials for separation may cause secondary pollution to the environment due to their non-degradable properties. Herein, we report a facile method of preparation of a biodegradable composite filter that can achieve filtration for air by underlaying the commercialized cellulose paper towel under electrospun zein fibers. The morphology of zein fibers was successfully steered via varying the weight ratios of ethanol/deionized water mixture solvent, as a result, the round or flat ribbon fibers were obtained. The effect of zein fiber morphology on air filtration performance was investigated both experimentally and theoretically. It was found that the flat ribbon fiber filter had a higher filtration efficiency (99%) for PM0.3 removal and a lower pressure drop (109 Pa) compared with the round zein fiber filter. Notably, the as-prepared composite filter can be biodegradable easily, contributing to green ecological environment. This work shows an efficient way to develop biodegradable filtration materials with the cheap price, easy availability of component materials, exhibiting a great potential application in air filtration area.