Application of PDMS pervaporation membranes filled with tree bark biochar for ethanol/water separation

Abstract

In order to improve separation performance of pervaporation membranes, we explored, for the first time, using tree bark biochar (BB) as filler for preparing polydimethylsiloxane (PDMS) composite membranes to separate ethanol from water. The composite membranes prepared by adding BB fillers obtained from different temperatures had different pervaporation performances. It was found that the addition of the three types of modified BB particles could all significantly improve pervaporation performance of the composite membranes. However their effects on permeation flux and separation factor were varied. Compared to BB obtained at 300 °C and 900 °C, BB obtained at 600 °C resulted in the membrane with the highest pervaporation performance with a separation factor of 9.92 and a permeation flux of 219.20 g m⁻² h⁻¹ at 40 °C in 10% ethanol solution. This study demonstrates the promise of biochar as a novel type of biomass-derived nanoparticles suitable for applications in pervaporation separation membranes.