Feasibility of Accessing Safe Water in Developing Countries Using Photocatalytic Technology—A Review

Abstract

Access to clean drinking water is a global concern. Notably, over one billion people in developing countries out of a total global population of approximately eight billion encounter challenges in accessing safe water. Photocatalytic technology is a potential solution for providing safe drinking water to these communities. However, only a few photocatalytic technologies are currently available. Although the potentialities of the photocatalytic treatment of water pollutants can be demonstrated in the laboratory, several factors hinder its effectiveness in real environmental applications. Additionally, the development of maintenance-free photocatalytic systems that can operate continuously without requiring complex maintenance is limited. Developing countries are unlikely to implement a system if it cannot be used sustainably without complex and/or frequent adjustments, regardless of the advanced technology. This principle is the fundamental premise of this review. This review in which are discusses the conditions necessary for photocatalytic water purification systems to be accepted in developing countries and explores how these systems can be successfully implemented.

Keywords

Photocatalyst / Drinking water / Water purification / Developing country / Water Matrix / Photocatalytic system

Acknowledgments

The authors would like to express their gratitude to Charinpanitkul of Chulalongkorn University, Chawengkijwanich and Pimpha of NANOTEC, Larpkiattaworn of TISTR, and Sirichan of Bestrade Precision Ltd. in Thailand for their cooperation in the drinking water survey in Thai villages. We would also like to thank Kato, President of the Photocatalyst Materials Co. Ltd., for his assistance in supplying a raw material for ceramic photocatalyst. We would like to thank Yamano and Ishii of Chiba Institute of Technology for their cooperation in the synthesis of ceramic photocatalysts and aragonite nanoneedles. We would also like to thank Miyazaki of our laboratory for conducting a large number of experiments in the treatment of bacteria in an aqueous phase.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data is available on request.

Funding

Declaration of Competing Interest

The author declares that they have no competing financial interests or personal relationships that may have influenced the work reported in this study.

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