Immobilizing laccase to cellulose-biochar composite beads for removing phenol from an aqueous system

Novel modified cellulose/biochar beads (MCBBs) were prepared and utilized as support to immobilize laccase to remove phenol from an aqueous system. Nano CaCO 3 was introduced in CBBs prepared stage to produce proper pore structure by reacting with HCl solution. CBBs were then modified with maleic anhydride to introduce carboxyl groups. By adsorption and covalent bonding, the laccase was immobilized on the MCBBs. The pH, laccase concentration, and contact time were chosen as the main parameters in the laccase immobilizing experiment and the effects of these parameters on immobilization rates and recovered activity were studied. The results demonstrated that the best conditions are: pH 4.0, concentration 8 g L –1 , and contact time 6 h. The thermal and operational stability of the immobilized laccase has attended a good performance under these conditions. The immobilized laccase was used to degrade phenol in an aqueous system and 40.97% removal was achieved after 72 h. The results suggest that as a new green material, MCBBs can be good support for immobilizing laccase. This technique has potential advantages in removing phenol from wastewater.