Low-cost, local production of a safe and effective disinfectant for resource-constrained communities

Abstract

AbstractImproved sanitation and hygiene depend on the accessibility and availability of effective disinfectant solutions. These disinfectant solutions are unavailable to many communities worldwide due to resource limitations, among other constraints. Safe and effective chlorine- based disinfectants can be produced via simple electrolysis of salt water, providing a low-cost and reliable option for on-site, local production of disinfectant solutions to improve sanitation and hygiene. We report on a system (herein called “Electro-Clean”) that can produce concentrated solutions of hypochlorous acid (HOCl) using only low-cost and now widely accessible materials. Using only table salt, water, graphite welding rods, and a DC power supply, HOCl solutions (∼1.5 liters) of 0.1% free chlorine (i.e. 1000 ppm) can be safely produced in less than two hours at low potential (5 V DC) and modest current (∼5 A). Rigorous testing of free chlorine production and durability of the Electro-Clean system components, described here, have been verified to work in multiple locations around the world by our project team, including microbiological tests conducted in two different countries to confirm the biocidal efficacy of the Electro-Clean solution as a surface disinfectant. We provide cost estimates for making HOCl locally with this method in the USA, India, and Mexico. Our findings show that Electro-Clean is an affordable alternative to off-the-shelf commercial chlorinator systems in terms of first costs (or capital costs), and cost-competitive relative to the unit cost of the disinfectant produced. By minimizing dependence on supply chains and allowing for local production, the Electro-Clean production process has the potential for improving public health by addressing the need for high- strength disinfectant solutions in resource-constrained communities.