The Role of Catalytic Ozonation Processes on the Elimination of DBPs and Their Precursors in Drinking Water Treatment

Abstract

Formation of disinfection byproducts (DBPs) in drinking water treatment (DWT) as a result of pathogen removal has always been an issue of special attention in the preparation of safe water. DBPs are formed by the action of oxidant-disinfectant chemicals, mainly chlorine derivatives (chlorine, hypochlorous acid, chloramines, etc.), that react with natural organic matter (NOM), mainly humic substances. DBPs are usually refractory to oxidation, mainly due to the presence of halogen compounds so that advanced oxidation processes (AOPs) are a recommended option to deal with their removal. In this work, the application of catalytic ozonation processes (with and without the simultaneous presence of radiation), moderately recent AOPs, for the removal of humic substances (NOM), also called DBPs precursors, and DBPs themselves is reviewed. First, a short history about the use of disinfectants in DWT, DBPs formation discovery and alternative oxidants used is presented. Then, sections are dedicated to conventional AOPs applied to remove DBPs and their precursors to finalize with the description of principal research achievements found in the literature about application of catalytic ozonation processes. In this sense, aspects such as operating conditions, reactors used, radiation sources applied in their case, kinetics and mechanisms are reviewed.

Ozone application in different industries: A review of recent developments

“…This facilitates the subsequent degradation of aqueous and adsorbed contaminants, eventually converting these compounds to water and carbon dioxide (mineralisation) [94] . The extensive review by Beltran et al demonstrated the effectiveness of catalytic ozonation for the elimination of disinfection by-products in water treatment industries [95] . Laundry wastewater (from commercial textile treatment facilities) containing anionic, cationic and nonionic surfactants has also been effectively treated with ozone [3] ; up to 55 % removal of dodecyl benzene sulfonate has been reported in Rivera-Utrilla et al [96] via the application of ozonation and biodegradation, whereas, ∼95 % of nonylphenol was removed by ozonation (1 mg/L for 90 min) in the work of Wang et al [97] .…”

Transformation of Algal Toxins during the Oxidation/Disinfection Processes of Drinking Water: From Structure to Toxicity

“…TP11 can be activated by HO • to form nucleophilic TP12, which is unstable and decomposes to TP13, TP14/15, and TCM. 119 DCAN and TCAN are formed via C−N bond breaking (TP3), further dehydration, and chlorine substitution. 45,79,118 During chlorination of CYN, 5-chloro-CYN (5-Cl-CYN) was formed, which reacts with chlorine much slower than CYN.…”

Ozonización catalítica en el tratamiento de Contaminantes de Preocupación Emergente en aguas residuales: Un análisis bibliométrico

“…En 1906 se instaló el primer sistema de desinfección de aguas residuales municipales con O3 en Niza (Francia) y desde entonces, ha sido ampliamente utilizado con fines de desinfección, sobre todo en Europa, ya que el cloro, normalmente utilizado en la desinfección (cloración), produce compuestos orgánicos halogenados que fueron identificados como agentes potenciales de riesgo para la salud pública (9) . De esta manera, el O3 funciona como un tratamiento complementario a la cloración, eliminando no solo patógenos, sino también materia orgánica para inhibir la producción de compuestos halogenados de desinfección, usualmente tóxicos, los cuales se producen durante la cloración (22) .…”

“…Dependiendo de las condiciones del medio y del tipo de contaminante, el O3 actúa a través de dos tipos de reacción: directa o de tipo radical, los cuales se muestran en la Figura 4. Jeirani Z (14) La reacción directa se produce en puntos nucleofílicos por reacciones de adición en restos insaturados (enlaces de carbono dobles y triples), por transferencia de electrones o por transferencia de átomos de oxígeno, debido a que el O3 por sí solo tiene un alto potencial redox (2.08 V) (22,24) . Los productos de estas reacciones son la materia orgánica oxidada, O2, diferentes iones como el hidroperóxido (𝑂𝐻 2 − ) y los ozonuros (𝑂 3 − ), radicales como el hidroperoxil (• 𝑂𝐻 2 ) y sustancias como el peróxido de hidrógeno (𝐻 2 𝑂 2 ) (24) .…”