Application of low purity horseradish peroxidase enzyme to removal of oil from oily wastewater

AbstractApplication of low purity horseradish peroxidase (HRP) extracted from horseradish root for oil removal from oily wastewater was studied. Factors, such as oil concentration; contact time; HRP dose; H2O2 concentration; pH; temperature; Fe2+ ion concentration; and effect of emulsifier (Tween 80), were studied. Results indicate optimum HRP concentration for 20, 60, and 120 mg/L oil were 2 U/mL and pH 7.5. Removal efficacy of oil increased with an increase in H2O2 concentration at first, and reached maximum of 58.33% at H2O2 concentration of 4 mM, and then decreased. Temperature has significantly effect on oil removal. Presence of Fe2+ ion in mixture solution has no effect on enzymatic treatment. Results of this study were found to be independent of enzyme purity and therefore, it was possible to utilize crude enzyme preparation instead of purified one. Experimental data of initial reaction rates were fitted using analytical equation proposed by Michaelis–Menten.