6.2.7 Ozonation
Ozone is a widely recognised and effective oxidant that can chemically react with many natural and non-toxic molecules (Coca et al., 2016). The reaction is caused by other oxidants such as hydroxyl radicals (HO•), which are formed when ozone has side reactions with effluent organic matter (EfOM) components such as phenols or amines (Rizzo et al., 2019). Numerous studies have demonstrated that ozonation is highly effective in removing personal care products and pharmaceuticals, with most of these contaminants being successfully eliminated.  It is important to understand that ozone has a brief 1/2  life, and if its awareness exceeds about 23%, it will become risky (Shen et al., 2019). Ozone reveals selectivity, mainly targeting electron-wealthy rising contaminants ECs with deprotonating amine action such as sulfamethoxazole and trimethoprim, especially at low pH levels. In assessment, hydroxyl radicals (HO•) are non-selective and highly reactive, allowing them to attack a large spectrum of ECs, together with those proof against ozone, mainly at higher pH degrees (Rizzo et al., 2019; Gogoi et al., 2018; Barbosa et al., 2016; Sui et al.,2010) .