Access to safe water and sanitation contributes to improved health and helps prevent the spread of infectious disease. Climate impact and freshwater scarcity pose an increasing challenge to access safe, clean water and will only exacerbate in the future. Furthermore, aging public water infrastructure, new pollutants of concern (for example, viruses, bacteria and an ever increasing list of toxic chemicals) and increasing household numbers require more distributed drinking water treatment. Current solutions are inadequate in that, they are:
Researchers led by Prof. Haizhou Liu have invented a next generation, light-emitting diode (LED) based chemical water purifier. The technology utilizes LED-based ultraviolet light and a photosensitizing chemical to disinfect and treat water, followed by a media filtration unit. UV light together with catalyst precursors is used to produce a group of photocatalysts (i.e., radicals) which include hydroxyl ion (OH-), free chlorine ion (Cl-), chlorine dimer (Cl2-) and amino radicals (NH2-). These radicals are reactive chemical species that attack pathogens, organic contaminants and inorganic contaminants.
Results from experimental testing of this innovative water purification system
|Contaminant Category||Model Contaminant||Concentration in feed water||Concentration in treated water||Removal Percentage|
|Pathogens||Pathogenic E. coli strain O157-H7||5 x 104 cells/mL||(5 ± 2.5) x 102 cells/mL||99 ± 0.5%|
|Organic Contaminant||1.4-dioxane||20 µg/L||0.6 ± 0.2 µg/L||97 ± 1%|
|Inorganic Contaminant||Lead||102 µg/L||1.6 ± 1.1 µg/L||98.5 ± 1.1%|
|Patent Cooperation Treaty||Published Application||WO 2023/081206||05/11/2023||2021-833|