Immobilization of laccase on magnetic bimodal mesoporous carbon and the application in the removal of phenolic compounds

A novel magnetically separable laccase immobilized system was constructed by adsorbing laccase into bimodal carbon-based mesoporous magnetic composites (CMMC). A large adsorption capacity (491.7 mg g−1), excellent activity recovery (91.0%) and broader pH and temperature profiles than free laccase have been exhibited by the immobilized laccase. Thermal stability was enhanced to a great extent and operational stability was increased to a certain extent. The shift of kinetic parameters indicated affinity change between enzyme and substrate. Application of the immobilized system in phenol and p-chlorophenol removal was investigated in a batch system. Adsorption effects of the support were responsible for the quick removal rate in the first hour, and up to 78% and 84% of phenol and p-chlorophenol were removed in the end of the reaction, respectively, indicating that the magnetic bimodal mesoporous carbon is a promising carrier for both immobilization of laccase and further application in phenol removal.

► A new laccase immobilized system was built using magnetic bimodal mesoporous carbon.
► Immobilized laccase exhibited excellent adsorption capacity and activity recovery.
► Immobilization improved reusability and resistance to pH and temperature changes.
► Nearly 80% of phenols were removed by the immobilized laccase in 12 h.
► Adsorption effects of the support mainly contributed to the first hour of removal.