Evaluation of Heterogeneous Photocatalysis for the Elimination of Microbiological Contaminants in Groundwater: Case of La Horca Sector, Chucarapi - Arequipa (#935)

Authors

Cabrera Choccata, Daysy Yanina

Calisaya Machaca, Luis Alfredo

Abstract

Microbiological contamination in groundwater represents a risk to public health, especially in rural areas such as La Horca, Anexo Chucarapi, Islay. This study evaluated the efficacy of heterogeneous photocatalysis using titanium dioxide (TiO₂) as a catalyst to remove total and fecal coliforms in well water. A hybrid photocatalytic reactor was designed, and 400 ml samples were treated at temperatures between 21 °C and 23 °C, with exposure times from 30 to 120 min. Contamination was measured by most probable count (MPN/100 ml) of total and fecal coliforms, following DIGESA protocols. The results indicated a maximum reduction of 93.27% for total coliforms and 92.27% for fecal coliforms, reaching levels close to the regulatory limits for fecal coliforms. However, total coliforms did not always meet the established standards, showing the need for optimization. Increasing time and temperature showed positive effects on removal, confirming the progressive efficacy of the treatment. These findings are consistent with previous research on the ability of heterogeneous photocatalysis to improve microbiological water quality. It is recommended that full-scale pilot studies be implemented and that this technology be combined with other treatments to fully meet sanitary standards.