Aluminum foil immersed in alkalized seawater removes Escherichia coli from household drinking water

Abstract

The contamination of drinking water by pathogens poses a serious health hazard in developing countries. Herein, a simple sanitization tool for drinking water is proposed using layered double hydroxide (LDH), which adsorbs most pathogens with its positive charges. By immersing aluminum foil in a mixture of seawater and NaOH without heating, a Mg–Al type LDH was directly formed and adhered to the surface (LDH foil). An LDH foil of 20 cm2 was shaken in 100 mL of test water containing Escherichia coli (DH5α) for up to 24 h and manually removed from the water. The initial viable count of approximately 103 CFU mL−1 decreased to 14 CFU mL−1 in 1 h, reaching 0.25 CFU mL−1 in 24 h; without the LDH foil, the variation 980–1,270 CFU mL−1. The simplicity in its development and use makes LDH foil a promising tool for sanitizing household water among rural residents. HIGHLIGHTS A foil with Mg–Al LDH directly formed on the surface was created from aluminum foil (LDH foil).; LDH foil adsorbed most of the Escherichia coli species (DH5α) from water.; LDH foil is easily removed from treated water.; LDH foil has the potential to be a sanitization tool for batch water, such as household jug water.;

Keywords

• adsorption
• drinking water
• escherichia coli
• layered double hydroxide
• removal