Solar evaporation enabled household ethanol distillation and disinfection system for remote area

Abstract

Ethanol concentrations of 70 %–90 % are commonly used to prevent healthcare-associated infections due to their effectiveness against various pathogens. However, high costs and transportation challenges limit the availability of commercial ethanol disinfectants, particularly in low- and middle-income countries. Local recycling of waste ethanol could address these issues, but large-scale implementation is hindered by the need for specialized equipment. Here, a small-scale, solar-powered ethanol recycling and disinfection device designed for household use was developed. Recycled melamine sponges, coated with polydopamine, serve as solar evaporators. The system achieves high evaporation rates (1.52–7.54 kg m⁻² h⁻¹) for ethanol solutions ranging from 0 % to 100 %. Through multiple distillations, dilute ethanol can be concentrated to the required levels for medical disinfection. A closed-loop system recycles waste ethanol, and outdoor tests demonstrate its effectiveness in eliminating Escherichia coli and Candida albicans using solar-generated ethanol vapor. This work offers a sustainable solution for small-scale ethanol distillation and disinfection in remote areas.