Laccase-carrying electrospun fibrous membrane for the removal of polycyclic aromatic hydrocarbons from contaminated water

Four types of laccase-carrying electrospun fibrous membranes (LCEFMs), with high laccase-catalytic activity and sorption capacity, were fabricated by emulsion electrospinning. These LCEFMs were composed of beads-in-string structural fibers, with nanoscale pores distributed on the surface and active laccase encapsulated inside. This obtained structure could protect laccase from external disturbance, resulting in that all of the four LCEFMs retained more than 70% of activity relative to free laccase, and after glutaraldehyde treatment, their storage and operational stabilities were definitely improved. The retained activities and stabilities of the LCEFMs were closely related to the hydrophilic–hydrophobic property of the polymer. Moreover, these LCEFMs possessed high adsorptivity for polycyclic aromatic hydrocarbons (PAHs), and the sorption capacities and rates were mainly influenced by the specific surface area of the LCEFMs and the hydrophilic–hydrophobic property of the polymer. The sorption of PAHs on the LCEFMs could significantly enhance their degradation efficiencies by laccase, which was obviously higher than those by free laccase. A mechanism of PAH degradation promoted by sorption was proposed.

► We prepared beads-in-string structural fibrous membranes by emulsion electrospinning. ► Active laccase could be successfully encapsulated in the core of beads. ► The membrane had functions of adsorption and biocatalysis simultaneously. ► The performances of membrane depended on its morphology and material. ► The degradation of PAHs was obviously promoted by their sorption.