Advanced treatment of industrial wastewater by ozonation with iron-based monolithic catalyst packing: From mechanism to application

An Fe-based catalyst was prepared by oxidising waste Fe shavings directly in a solution. In engineering applications, Fe shavings were compressed and modified to form Fe-based monolithic catalyst packing. Both of which exhibited excellent catalytic activity in catalytic ozonation industrial wastewater after biochemical treatment. Fe-based monolithic catalyst packing has irregular channels, large porosity, small pore diameter, and the effective specific surface area (SSA) up to 3500 m2/m3, these characteristics are conducive to mass transfer, and promote the effective utilisation of •OH in the catalyst “action zone”. A tower reactor (<3000 m3/d) and reinforced concrete construction reactor (>5000 m3/d) were designed according to the wastewater flow. Regression analysis showed that hydraulic residence time (HRT) and O3/CODin are important parameters in engineering design and operation. In addition, strategies for the application of Fe-based monolithic catalyst packing to wastewater with high salinity and high inorganic carbon concentration have been proposed. Fe-based monolithic catalyst packing catalytic ozonation is a relatively cost-effective and eco-friendly process with extremely broad application prospects in the advanced treatment of industrial wastewater.