Microplastics enhance laccase-driven bisphenol A removal in multipollutant wastewater.

Abstract

Bisphenol A (BPA) is recognized as a significant constituent of environmental pollutants and could be efficiently removed from wastewater by laccase (Lac). Microplastics (MPs) was found to be present in wastewater contained BPA. This work was to realize BPA removal from wastewater in the presence of MPs by Lac and to reveal the possible mechanism for MPs enhancing Lac-driven BPA removal. BPA removal by Lac increased with 96.1 ± 0.3 % when BPA was in the presence of Polyethylene (PE). Lac can improve the adsorption capacity and adsorption rate of BPA by PE, and PE can enhance the degradation of BPA by Lac. Furthermore, K_i and C_i values were 14.237 and 25.091 when BPA removal by Lac in the presence of MPs, indicating that the diffusion rate of BPA was accelerated. The ΔS₀ was increased 0.064 kJ mol^-1·K^-1 by Lac in the presence of PE, indicating that the solid-liquid interface reaction efficiency was also improved. The particle size, dosage, and type of MPs were shown different promoting effects on BPA removal by Lac. The introduction of ultrasound (UL) and micro-nano bubbles (MNB) further promotes BPA removal in the presence of MPs by Lac, and BPA removal were increased by 20.5 ± 0.8 % and 46.6 ± 0.7 %, respectively. The initial BPA concentration, Lac concentration, and pipe length on BPA removal in the presence of PVC were investigated by MNB synergistic Lac. BPA removal with MNB-Lac in the presence of PVC was 91.5 ± 0.8 % under the optimal conditions. This study has the unique advantage of exploring the effect and mechanism for BPA removal by Lac in the presence of MPs, and providing insights for the subsequent treat actual water bodies containing MPs by enzyme.