Use of Immobilized Enzyme In Granular Activated Carbon And Chitosan Beads For Phenol Removal From Effluents
Abstract Tyrosinase enzyme present in a crude extract was immobilized in granular activated carbon (GAC) and activated chitosan beads (ACB). It was possible to immobilize up to 70.0 % of the enzymes in GAC in the conditions of 10.0 g of support, 15.7 rad/s of agitation and 90 minutes of contact time, and 100.0 % of enzymes in ACB when using 5 g of support, agitation of 15.7 rad/s and contact time of 120 minutes. In enzymatic oxidation tests, tyrosinase immobilized in GAC was able to achieve a final phenol concentration below the limit required by Brazilian law, 0.5 mg/L for phenol solutions with an initial concentration up to 20.0 mg/L while the enzyme immobilized in ACB was able to adapt solutions with initial concentrations of phenol up to 40.0 mg /L. It was possible to reuse the enzyme immobilized in GAC 2 times, maintaining the same phenol removal efficiency, while the enzyme immobilized in ACB maintained up to 98.0 % of its efficiency in 5 cycles of enzymatic oxidation of solutions with 10.0 mg/L of phenol initially. It was possible to maintain the same phenol removal efficiency as immobilized enzymes when stored for up to 2 weeks.