Main Article Content
photocatalysis, TiO2, disinfection, inorganic salts, kinetic.
This article presents the eﬀect of inorganic salts MgSO4, NaCl and CaCO3 on the photocatalytic water disinfection. TiO2-P25 was used as a photocatalyst, and E. Coli was used as a contaminant. Disinfection tests were performed by controlling lighting of batch reactors loaded with contaminated water, salts and TiO2. The results of these tests were used to determine the kinetic parameters of a type Langmuir-Hinshelwood model. It was found that the salts have a strong inﬂuence on the photocatalytic inactivation of E. Coli and that each salt and its concentration aﬀect disinfection diﬀerently in the following order: NaCl>CaCO3>>MgSO4. Additionally, the value of the calculated parameters was diﬀerent for each salt, showing that the salts aﬀect the process by several mechanisms related to the ion-bacteria interactions, ion-oxidizing species and ion-TiO2.
PACS: 82.65..+r, 61.82.Fk, 82.50.-m
MSC: 65c20, 34-99
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