Fe0Ni0 Bimetal Co-Immobilized Horseradish Peroxidase on ZIF-8@HMON for Degradation of Trichloroacetic Acid

As a common pollutant in the environment, trichloroacetic acid (TCA) is difficult to be completely degraded by common advanced oxidation processes (AOPs) due to its high C-Cl bond content. Advanced oxidation-reduction processes (AORPs) may improve the degradation performance of TCA. In this work, we use (FeNi0)-Ni-0 bimetal as reducing catalyst, hollow mesoporous silicone nanoparticles (HMONs) modified by ZIF-8 as immobilized carrier, horseradish peroxidase (HRP) and (FeNi0)-Ni-0 were fixed in the carrier to form a AORP system for degradation of TCA. The effects of temperature, pH, H2O2 concentration, doping ratio on the degradation performance of the catalyst and the degradation mechanism of the composite catalyst were investigated. Degradation experiments showed that H and OH were present in the dual system, dechlorination and decarboxylation exist at the same time. Under the condition of 55 degrees C and pH = 4, 30 mg (FeNi0)-Ni-0 and 20 mg immobilized enzyme shows the best degradation on TCA, and 81.48 % of 20 mgL-1 TCA could be degraded by 2 h.