An on-Site, on-Demand, Medium-Sized Hypochlorous Acid Maker for Covid-19 Control
Authors: LI Liyu 
Published: July 2021

Hypochlorous acid (HOCl) is an endogenous substance and has been proven effective against many microorganisms1. It has been shown that HOCl can inactive numerous viruses, including Corona-19 Viruses in less than one minute1. HOCl already has applications in numerous industries such as farming, hospitality, food, healthcare including disinfection and wound care1. HOCl inactivates viruses, bacteria, endospore and fungi whilst being safe for human tissues with a 99.999% elimination rate2. HOCl is listed on the United States Environmental Protection Agency’s List for Disinfectants for Use Against SARS-CoV-2 (Covid-19)3. It can be used conveniently as hand sanitizer, surface cleanser, food washing solution, fogging solution for school classrooms, buses, shops, restaurants, hotels, offices, theaters, airports, trains, gyms, etc. It is a green, safe, environmentally friendly and fully biodegradable liquid which acts as a very powerful antimicrobial and sterilizing solution4-6.
However, the pre-made HOCl hypochlorous acid products in the market are expansive, mostly due to high cost for packaging, transportation, distribution, storage, and in-stability of the product, which normally has a lifetime of 6 -12 months. The capacity of current on-site HOCl generation products is either too big, or too small, only economical for large quantity consumers or single household uses. Due to the Corvid-19 pandemic, there is a strong need for a safe, on-site, on-demand medium-sized HOCl generation product, which uses only non-hazardous household chemicals and has a production capacity of about 10 gallons per day. Here we report our recent development of a compact and low cost HOCl on-site generator for daily disinfection applications against Corvid-19 virus. Compared to other products on the market, which normally use >2 g/L NaCl solutions, our device uses only 0.4 g/L NaCl solution. This is highly desired for environment fogging disinfection applications. Other advantages include: 1) no noticeable Cl2 gas generation during HOCl production; 2) tap water can be used directly without softening treatment; 3) produce very stable products, with 90% HOCl Stability: > 100 days.

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Agency, U. S. (2020, July 1). List N: Disinfectants for Use Against SARS-CoV-2 (Covid-19O). Retrieved from United States Environmental Protection Agency: https://www.epa.gov/pesticide-registration/list-n-disinfectants-use-against-sars-cov2-covid-19

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https://www.hypochlorousacid.com

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