Polycarbonate and activated charcoal-engineered electrospun nanofibers for selective recovery of oil/solvent from oily wastewater

Abstract

Present study reports polycarbonate (PC) nanofibers functionalized with industrial grade activated charcoal for emphatic oil–water separation and recovery of petroleum oils and organic solvents from oily wastewater. The developed PC nanofibers demonstrate hydrophobicity (water contact angle of 133°) and oleophilicity (oil and/-or solvent contact angle is equal to 0°), simultaneously. The functionalized PC nanofibers exhibit average permeation flux of 10,834.5 L m−2 h−1 and 39,886.5 L m−2 h−1 toward diesel, and n-Hexane solvent, respectively. Developed PC nanofibers demonstrated an excellent oil recovery toward petroleum oil products like petrol, diesel, and engine oil, which was found to be 308%, 872%, and 1738%, respectively, till 10 washing cycles. Thermogravimetric analysis of developed PC nanofibers revealed thermal stability up to 350 °C, thereby demonstrating its applicability in harsh environmental conditions. Functionalization of PC polymer nanofibers with activated charcoal was confirmed using FTIR study. The morphological analysis of charcoal functionalized PC nanofibers revealed a heterogeneous rough patterned textures with a porosity (which facilitate the air-pockets for improved hydrophobicity) manifesting inside the fibers. The pH-based performance (pH range of 2–14) demonstrated that the developed microfibers maintain its hydrophobicity ad service durability under harsh acidic and alkaline mediums (corrosive environments). The PC nanofibers demonstrate simultaneous hydrophobic–oleophilic behavior which is well explained using principal Cassie–Baxter’s theory. The successive results demonstrate that the activated charcoal functionalized PC microfibers could be successfully utilized for practical recovery of oil/organic solvents from oily wastewater, and for the oil-spill cleanups.