By-product class

Description

Electrolysis By-Products (EBPs)

Electrolysis by-products (EBPs) are the consequence of undesirable electrochemical reactions such as the anodic chlorate and the cathodic nitrite and ammonia formation [101] :

6HClO + 3H₂O → 2ClO₃⁻ + 4Cl⁻ + 12H⁺ + 3/2O₂ + 6e⁻ (6)

${\text{NO}}_{\text{3}}^{-}$ + H₂O + 2e⁻ → ${\text{NO}}_{\text{2}}^{-}$ + 2OH⁻ (7)

${\text{NO}}_{\text{2}}^{-}$ + 5H₂O + 6e⁻ → NH₃ + 7OH⁻ (8)

Disinfection By-Products (DBPs)

As portion of electrolytes, organic matter is mainly classified as Natural Organic Matter (NOM) [102] [103] [104] , Total Organic Carbon (TOC) [105] [106] [107] , and Dissolved Organic Carbon (DOC) [108] [109] [110] . They are typical precursors for the famous “Disinfection By-Products (DBPs)” [110] [111] [112] . Familiar from chemical disinfection [113] [114] [115] , DBPs are generated from reacting disinfectants with pollutants present in water [116] . In ED for drinking water, identical DBPs were detected when juxtaposed to chemical chlorination [53] [116] [117] . Reacting pathogen cell mater could be a supplementary source of DBPs (Figure 4) [118] [119] [120] .

Reaction By-Products (RBPs)

Reaction By-Products (RBPs) constitute all residual reactions in the electrode layers and bulk of solution. As an illustration is the chemical chlorate generation from free active chlorine species or from chlorite ions [118] .