Hand-powered and portable water disinfection system by locally enhanced electric field treatment (LEEFT) with modified nanowire electrodes

Disinfection of drinking water is essential to protect human lives. Mostly used disinfection technology is chlorination which produces carcinogenic by-products. The other technologies are UV and membrane filtration, which require high-energy input, and none of them are portable. In the present study, we have studied a hand-powered, portable, low-cost, low-energy input disinfection system. It contains a hand-operated electromagnetic generator as power source and a copper tube with coaxial modified copper oxide nanowires electrode as water disinfection interface through electric field. Bacteria and viruses can be inactivated by applying an electric field of the order 1–10 kV cm−1. Nanowires can enhance local electric field at its tip, by lightning rod effect. In addition to that, microbiological cell can be inactivated by low-voltage input. Electromagnetic generator used in this device generates 5.34 Vrms (connected to device filled with 20 ml water) by rotating it at 100–110 rpm. Disinfection efficiency was tested on Escherichiacoli (E. coli) and Staphylococcusaureus (S. aureus). Log inactivation efficiency of the order of 4 and 5 was obtained on E. coli and S. aureus, respectively, in 5 min of treatment time.