Influence of the Support Modification Methods on the Chlorophenol Utilization by the Peroxidase Immobilized on Titanium Dioxide

Abstract

In the current work, the synthesis of the effective multicomponent biocatalysts on the base of horseradish peroxidase immobilized on the modified titanium dioxide for the utilization of chlorophenolic water contaminants was performed. The influence of the support modification methods on the biocatalyst activity and stability was studied. The immobilization of horseradish peroxidase on the unmodified titanium dioxide was found to be ineffective due to the high losses in the enzyme amount during the reaction as well as the biocatalyst particles aggregation (the activity reduces more than 95 %). The titanium dioxide surface modification by the sodium alginate and carbodiimide (23.5 % activity in comparison with the native enzyme); hydrochloric acid, chitosan and glutaric dialdehyde (33.7 % activity in comparison with the native enzyme); and hydrochloric acid, chitosan, glutaric dialdehyde and aminopropyltriethoxysilane (42.5 % activity in comparison with the native enzyme) were found to be the most effective methods. Besides, the last two biocatalysts showed high stability in 10 consecutive cycles. The synthesized biocatalyst can be effectively used for the removal of chlorophenols from the wastewater until the concentrations of 10 ppm.