HRP Immobilization on Activated Carbon/Polyvinyl Formal Composite Materials for Degradation of Phenolic Wastewater

Abstract

A novel method was developed for degradation of phenolic waste water using horseradish peroxidase (HRP) immobilization on activated carbon/polyvinyl formal (AC/PVFM) composite materials in this study. The materials were black-sponge-like, soft and elastic, and had three-dimensional porous network structure. Optimum conditions of immobilized HRP carrier preparation technology was selected by orthogonal experiment. The enzymatic properties were explored and compared between immobilized and free enzyme. The optimum pH of immobilized HRP and free HRP were both 4, nevertheless, the immobilization of HRP increased the enzyme activity. The optimum temperature of immobilized HRP was 20°C which was lower than that of free HRP (25°C), therefore the immobilized HRP could resist to lower temperature. The Km of immobilized HRP and free HRP were 0.23 mmol/L and 0.40 mmol/L, respectively. The lower Km value of immobilized HRP indicated higher affinity to the substrate. These results show that HRP immobilized on AC/PVFM composite materials is promising in phenolic wastewater degradation.