Porous ceramic tablet embedded with silver nanopatches for low-cost point-of-use water purification.
This work describes a novel method to embed silver in ceramic porous media in the form of metallic silver nanopatches. This method has been applied to develop a new POU technology, a silver-infused ceramic tablet that provides long-term water disinfection. The tablet is fabricated using clay, water, sawdust, and silver nitrate. When dropped into a household water storage container, the ceramic tablet releases silver ions at a controlled rate that in turn disinfect microbial pathogens. Characterization of the silver-embedded ceramic media was performed using transmission electron microscopy. Spherical-shaped patches of metallic silver were observed at 1–6 nm diameters and confirmed to be silver with energy dispersive spectroscopy. Disinfection experiments in a 10 L water volume demonstrated a 3 log reduction of Escherichia coli within 8 h while silver levels remained below the World Health Organization drinking water standard (0.1 mg/L). Silver release rate varied with clay mineralogy, sawdust particle size, and initial silver mass. Silver release was repeatable for daily 10 L volumes for 154 days. Results suggest the ceramic tablet can be used to treat a range of water volumes. This technology shows great potential to be a low-cost, simple-to-use water treatment method to provide microbiologically safe drinking water at the household level.
Department of Civil and Environmental Engineering, University of Virginia, Charlottesville, Virginia 22904, United States.
Beeta
B
Ehdaie
Carly
C
Krause
James A
JA
Smith
D002516:Ceramics / Q000737:chemistry*; D004202:Disinfectants / Q000737:chemistry / Q000191:economics; D004203:Disinfection / Q000191:economics / Q000379:methods; D004926:Escherichia coli / Q000302:isolation & purification; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D012834:Silver / Q000737:chemistry*; D014871:Water Microbiology; D018508:Water Purification / Q000191:economics / Q000295:instrumentation* / Q000379:methods*
D004202:Disinfectants; D012834:Silver