Coalescence performance of Janus filter for the removal of oil mist

The wettability has an important effect on coalescence performance of filter. In this paper, we utilized a commercial glass fiber filter as the substrate to prepared the Janus filter through dip-coating and electrospraying. The Janus filter exhibited a remarkable reduction in pressure drop, with only 2.8 kPa of wet pressure drop compared to 6.1 kPa for the original filter and 5.4 kPa for the oleophilic filter. Notably, the coating depth played a critical role in enhancing the coalescence performance of the Janus filter. Furthermore, when placing the Janus filter in reverse direction, its quality factor increased by 2.87 times, highlighting that orientation is an essential factor for coalescence performance of Janus filters. The results indicate great potential in the application of Janus filters for coalescence filtration.