High performance persistent organic pollutants removal using stabilized enzyme aggregates over amino functionalized magnetic biochar

Herein, a highly efficient and recyclable biocatalyst was developed using stabilized enzyme aggregates on amino-functionalized magnetic biochar for removing persistent organic pollutants from water. The biochar derived from biomass featured abundant hydroxyl functional groups, after functionalization with amino functional groups and magnetic nanoparticles, it was employed for laccase immobilization via enzyme electrostatic adsorption, precipitation and cross-linking in a favorable orientation. This immobilized enzyme aggregates exhibited enhanced pH tolerance, thermal and storage stability than free enzyme. Complete removal of 20 mg/L bisphenol A was achieved within 60 min via C-C bond cleavage and hydroxylation. Notably, the removal efficiency remained at approximately 90 % even after six cycles. Furthermore, this biocatalyst was also successfully applied to efficiently remove other various persistent organic pollutants and demonstrated applicability in real environmental water samples. This study highlights the substantial potential of enzyme-based biocatalysts, presenting a sustainable and efficient approach for water purification and biomass resource recovery.