As a result, many research groups around the world have been pursuing approaches to developing some form of portable hydrogen peroxide production equipment.
Most of the hydrogen peroxide produced in the industrialized world is made in large chemical plants, where methane, or natural gas, is used to provide a source of hydrogen, which is then reacted with oxygen in a catalytic process under high heat.
This process is energy-intensive and not easily scalable, requiring large equipment and a steady supply of methane, so it does not lend itself to smaller units or remote locations. Other processes developed so far for potentially portable systems have key limitations. For example, most catalysts that promote the formation of hydrogen peroxide from hydrogen and oxygen also make a lot of water, leading to low concentrations of the desired product.
Also, processes that involve electrolysis, as this new process does, often have a hard time separating the produced hydrogen peroxide from the electrolyte material used in the process, again leading to low efficiency.
Surendranath and the rest of the team solved the problem by breaking the process down into two separate steps. This molecule — a compound called anthroquinone, in these initial experiments — is then introduced into a separate reaction chamber where it meets with oxygen taken from the outside air, and a pair of hydrogen atoms binds to an oxygen molecule O2 to form the hydrogen peroxide. In the process, the carrier molecule is restored to its original state and returns to carry out the cycle all over again, so none of this material is consumed.
The process could address numerous challenges, Surendranath says, by making clean water, first-aid care for wounds, and sterile food preparation surfaces more available in places where they are presently scarce or unavailable. So, for example, a portable hydrogen peroxide plant might be set up adjacent to a fracking or mining site and used to clean up its effluent, then moved to another location once operations cease at the original site.
In this initial proof-of-concept unit, the concentration of hydrogen peroxide produced is still low, but further engineering of the system should lead to being able to produce more concentrated output, Surendranath says.
Even dried and decomposed blood gives a positive reaction with the blue glow lasting for about 30 seconds per application. The glow can be documented with a photo but a fairly dark room is required for detection. The reaction is so sensitive that it can reveal blood stains on fabrics even after they have been laundered. In one case, a pair of washed jeans with no visible stains gave a positive test with luminol on both knees.
Neither the Kastle-Meyer test nor the luminol test can identify whose blood is involved, but once a stain has been determined to be blood, traces of DNA can be extracted and an identification carried out. In the example of the jeans, DNA analysis was able to exclude the blood coming from the owner of the jeans.
Luminol analysis does have drawbacks. Its chemiluminescence can also be triggered by a number of substances such as copper-containing compounds and bleaching agents. Had the jeans been washed with a detergent containing a bleaching agent, the blood would not have been detected. Criminals aware of this have been known to try to wash away traces of their crime with bleach. The result is that residual bleach makes the entire crime scene produce the typical blue glow, which effectively camouflages any blood stain.
And if you want to see a really impressive glow, spray a piece of liver with a luminol test solution. In the 's, hydrogen peroxide was first used for drinking water disinfection in Eastern Europe. It is known for its high oxidative and biocidal efficiency. Hydrogen peroxide has not been used often for drinking water disinfection, but it's popularity seems to increase.
It is often used combined with ozone , silver or UV. Is hydrogen peroxide used for swimming pool disinfection? The application of peroxides for disinfection and water treatment are limited. Recently, more stable forms have been developed, which can be used for application in swimming pools. Hydrogen peroxide disinfection requires a high dose. The main disadvantage is the small disinfecting and oxidising ability of hydrogen peroxide at active concentrations tens of milligrams per litre , which are required for swimming pool disinfection.
Another problem is the quick decomposition of hydrogen peroxide in water and the presence of oxygen radicals. Through stabilizer addition, the decomposition of hydrogen peroxide is delayed and the disinfection ability can be maintained. Compared with chlorine , bromine , ozone and other disinfectants, hydrogen peroxide is not a very powerful disinfectant.
Swimming pools disinfection by hydrogen peroxide is not allowed, unless it is used in combination with other disinfectants UV, ozone, silver salts or ammonia quart salts.
Hydrogen peroxide improves the disinfection ability of other disinfectants. Can hydrogen peroxide be used for cooling tower water disinfection? Hydrogen peroxide can be used for cooling tower water disinfection, when it is combined with other disinfectants. Does hydrogen peroxide remove chlorine? Hydrogen peroxide can be used for dechlorination, in other words to remove residual chlorine.
Residual chlorine forms corrosive acids when it is oxidised by air or condensates on process systems. When chlorine reacts with hydrogen peroxide, hydrogen peroxide falls apart into water and oxygen. Chlorine gas hydrolyses into hypochlorous acid HOCl , which subsequently ionises into hypochlorite ions OCl. Other organic and inorganic substances cannot react with hypochlorite.
What are the advantages and disadvantages of hydrogen peroxide use? Contrary to other chemical substances, hydrogen peroxide does not produce residues or gasses. Safety depends on the applied concentration, because hydrogen peroxide is completely water soluble. Hydrogen peroxide is a powerful oxidizer. It reacts with a variety of substances. It is therefore diluted during transport, as a safety measure. However, for hydrogen peroxide disinfection, high concentrations are required.
Hydrogen peroxide slowly decomposes into water and oxygen. An elevation of temperature and the presence of pollutions enhance this process. The concentration of hydrogen peroxide in a solution slowly decreases.
Hydrogen molecules partly function as reductors and partly as oxidizers. Is hydrogen peroxide efficient? The efficiency of hydrogen peroxide depends on several factors, such as pH, catalysers, temperature, peroxide concentration and reaction time. Exposure to hydrogen peroxide takes place through inhalation of damp or mist, through food uptake and through skin or eye contact. Hydrogen peroxide can irritate the eyes, skin and mucous membranes.
Laboratory tests with bacteria show that hydrogen peroxide is mutagenic; it changes and damages DNA. When humans inhale hydrogen peroxide, it causes lung irritation.
Skin exposure causes painful blisters, burns and skin whitening. As you become acquainted with the many uses of peroxide, chances are you will discover more safe ways to take advantage of its natural cleaning and antibacterial benefits.
By subscribing you agree to the Terms of Use and Privacy Policy. Health Topics. Health Tools. Healthy Home. By Rose Alexander. Reviewed: November 15, Many consumers today are not familiar with the wide range of possible uses of peroxide, although most homes have a bottle of three percent solution among their home medical supplies.
Widely used as a disinfectant, peroxide medical uses extend beyond the occasional scrape or cut. Few products are as versatile, cheap, and effective as hydrogen peroxide. Although it can be toxic or even fatal when taken internally as a stronger solution, the common, everyday uses of peroxide are worth investigating while selecting home medical supplies and cleaning products. What is hydrogen peroxide? Known as chemical compound H, hydrogen peroxide is a powerful oxidizer that is stronger than chlorine, chlorine dioxide, and potassium permanganate.
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