Popular Science | New Green Bactericidal Disinfectant-Chlorine Dioxide

History of chlorine dioxide

CHLORINE DIOXIDE (CLO₂) WAS FIRST DISCOVERED IN 1811 BY THE AMERICAN CHEMIST HUMPHVY DAVID, AND IS A YELLOW-GREEN TO ORANGE-YELLOW GAS AT ROOM TEMPERATURE AND PRESSURE. In the 40s of the twentieth century, chlorine dioxide began to be used in sterilization and disinfection of food processing, bleaching of papermaking and purification of water.

In 1983, the U.S. Environmental Protection Agency (EPA) proposed that drinking water must contain less than 0.1mg/L chloroform and recommended the use of chlorine dioxide for disinfection. Carbon dioxide is classified as an A1 disinfectant by the World Health Organization (WHO) and is recognized as the most ideal replacement product for chlorine-based disinfectants. At present, developed countries such as the United States, Western Europe, and Canada have widely used chlorine dioxide for disinfection in food processing, pharmaceutical, and hospital public environments.

Chlorine dioxide was introduced to China in the 80s of this century, and in 1978, the Guangdong Provincial Health Supervision Department approved that it can be used for food disinfection, preservation and disinfection of food equipment and utensils. In 1990, the Shanghai health management department approved that it can be used for water treatment, food processing, aquaculture, deodorization, etc. In 2000, China's Ministry of Health also made it clear that chlorine dioxide would be used to gradually replace chlorine for drinking water disinfection.

Specific applications of chlorine dioxide

Almost all water plants in the United States and Western Europe have used chlorine dioxide to replace C12 for disinfection, which is characterized by: the water after disinfection tastes good, safe and non-toxic, can reduce toxic substances, and does not produce carcinogens, convenient to use, safe, and low comprehensive cost. It is estimated that only 1 ton of disinfectant is needed per 10,000 tons of water. In addition, at pH>7, chlorine dioxide can rapidly oxidize iron and manganese ions in water to form insoluble compounds; According to the experiment of Shanghai Water Supply Company, when the amount of chlorine dioxide is 1.2mg/L, it has the highest efficiency in removing manganese and iron in the water, and has the lowest effect on the color of the disinfected water

As a national fitness sport, swimming has become the people's favorite sport with the improvement of people's living standards. The quality of water quality is the most concerned problem of swimmers, chlorine disinfectant in the disinfection of swimming pool water at the same time, produce a great pungent odor, especially indoor swimming pool, swimmers often have red eyes, hair yellow; And the use of chlorine dioxide to disinfect swimming pool water, does not produce irritating odor, and removes odors, purifies water quality, and has more oxygenation effect, so that the indoor air of the swimming pool is fresh and the pool water is blue.

Chlorine dioxide as the fourth generation of aquaculture disinfectant, not only can greatly reduce the number of pathogenic microorganisms in the water, but also does not damage plankton, disinfection and oxygenation of water bodies, hemorrhagic septicaemia, rotten gills, red skin, enteritis, water mildew and shrimp solitary disease, virus disease and so on have significant curative effects, in recent years has been in Hainan, Guangdong, Shandong, Hebei and other coastal aquaculture areas rapidly popularized, and has gradually penetrated into the inland freshwater aquaculture areas.

After the 2% chlorine dioxide solution is activated, more than 12% of the chlorine dioxide gas will be emitted without dilution and quickly diffuse into space. When ρ (CIO2) in the air reaches 4mg/m³, it can kill more than 99.99% of all kinds of bacteria, viruses and molds, and can eliminate odor and peculiar smell, no irritation to the human body, and is more efficient and safer than formaldehyde and sulfur fumigation. In general, 20ml of activated chlorine dioxide solution can be used per cubic meter of space; When in use, the open container containing chlorine dioxide is placed at the position of 1~1.5 meters high from the ground indoors, and the open container containing chlorine dioxide is placed in 4 corners of the room and the middle position of the room, so that the chlorine dioxide gas is evenly emitted in the space; When in use, it can be replaced once every 2~3d, and the open containers in 5 positions in the room can be replaced in turn, so as to avoid replacing all of them at one time and causing the indoor odor to be too large in a short time, and the chlorine dioxide solution can be replaced once in turn about 10d.

In addition, chlorine dioxide can effectively remove formaldehyde in newly renovated and decorated rooms and newly purchased cars, and its mechanism of action is that chlorine dioxide can oxidize formaldehyde that makes people carcinogenic to non-toxic formalic acid, so as to achieve effective removal of aldehydes;

The application of chlorine dioxide in the crop planting industry was the earliest in Japan. Because it effectively kills all kinds of molds and viruses at the same time, there is no toxic substance residue, and it is highly respected in today's vigorous promotion of green health food. In China's Hebei Gaoyi, Shandong Shouguang and other vegetable and mushroom planting bases, have achieved successful experience and good economic benefits, especially in the greenhouse vegetables, mushrooms and other planting industries that are prone to disease are gradually popularized.

The principle of chlorine dioxide for air disinfection is to use the strong oxidation of chlorine dioxide to generate free oxygen after photolysis, oxidize the harmful substances in the air, destroy their activity, and make them unable to survive, so as to achieve the purpose of air disinfection. At present, there are chlorine dioxide finished stable disinfectants on the market that are specially used for air disinfection in public environments, which have no odor and residue for environmental disinfection, and have good disinfection effect.

Fengmi Technology has cooperated with the American team to develop a variety of nano-zeolite materials with different structures and sizes.

Zeolite is a skeleton material with high specific surface area, combined with the excellent sterilization and disinfection effect of chlorine dioxide, a safe and high-load chlorine dioxide solid slow-release material (nanochlorine) is synthesized, which effectively solves the problem that chlorine dioxide is prone to explosion at high concentrations. By manipulating the structure and properties of the carrier material, the team was able to control the rate of chlorine dioxide release and achieve sustained release for up to 3-6 months. It has changed the traditional way of using chlorine dioxide, and can be better used in specific application scenarios.

brief summary

Chlorine dioxide is not only a broad-spectrum environmentally friendly sterilization disinfectant, but also has significant effects in food preservation, deodorization and odor removal. The World Health Organization (WHO), the United States Environmental Organization (EPA), the Ministry of Health of China, etc., have recognized chlorine dioxide as a green disinfectant in the new era, with the characteristics of no three causes (no carcinogenicity, no teratogenicity, no mutagenicity), and three effects (broad-spectrum, efficient and fast), and has been compiled into health regulations for use.