Advances in the removal of precursors of disinfection by-products by ultraviolet-coupled advanced oxidation processes

Disinfection is an indispensable water treatment process to kill pathogens in water and prevent water-borne diseases. However, the disinfection by-products generated in the process have become the main cause of threats to human health and the ecological environment. Many studies have shown that removing the precursors of disinfection by-products is currently one of the most effective methods to reduce the production of disinfection by-products. Ultraviolet-coupled advanced oxidation processes can generate strong oxidizing free radicals through ultraviolet light activation to efficiently remove disinfection by-product precursors. It makes up for the deficiencies of traditional oxidation technology, has important significance in reducing the generation potential of disinfection by-products, and improving water quality conditions, with broad development prospects. This paper reviews the mechanisms and advances of several UV-coupled advanced oxidation processes for the treatment of disinfection by-product precursors, UV/ozone (UV/O-3), UV/hydroperoxide (UV/H2O2), UV/persulfate (UV/PS), UV/chlorine (UV/Cl-2) included. The treatment effects, advantages, and disadvantages of various advanced oxidation processes are compared, moreover, the future research directions and problems to be solved for the removal of disinfection by-products and precursors are proposed to promote the achievement of practical engineering application of UV coupled advanced oxidation processes.

Automated summary

Disinfection is essential for killing pathogens in water, but disinfection by-products pose threats to human health and the environment. Removing disinfection by-product precursors is an effective method, and UV-coupled advanced oxidation processes show great potential for development.