Hydrogen Peroxide (H2O2) is made up of two hydrogen atoms and two oxygen atoms. H2O2 is clear liquid, chemical compound and colorless, but that extra oxygen molecule makes this natural water additive one of the most powerful oxidizers liquid and capable of reacting explosively with combustibles. Used mostly in diluted water based solutions . Hydrogen peroxide was discovered (1818) by L. J. Thenard Although pure hydrogen peroxide is fairly stable, it decomposes into water and oxygen when heated above about 80°C; it also decomposes in the presence of numerous catalysts, e.g., most metals, acids, or oxidizable organic materials. A small amount of stabilizer, usually acetanilide, is often added to it. Being a powerful oxidizer, hydrogen peroxide kills bacteria, viruses and fungi Hydrogen peroxide has many uses. It is available for household use as a 3% (by weight) water solution; it is used as a mild bleaching agent, medicinally as an antiseptic and a laboratory reagent. Hydrogen peroxide is available for commercial use in several concentrations ranging from 27 – 90 %, usually 35%, 50% and 70%. 2 H 2O 2 —-> 2 H 2O + O 2 (hydrogen peroxide —-> Water + Oxygen)
Hydrogen Peroxide is a widely used chemical substance for manufacturing bleaching agents, oxidants, and derivatives. It has played a major role as a bleaching agent in fiber dyeing and pulp & paper industries. (Details) Textile industry Hydrogen peroxide is commonly used for textile bleaching, oxidizer, and desizing. It is widely used on natural cellulosic fibers (cotton, flax, linen, jute, etc.), protein fibers (wool, silk, etc.) and synthetic blends. Bleaching to high brightness with top fiber properties can be conducted in a multitude of different bleaching conditions . Hydrogen peroxide is also effective on regenerated cellulose fibers. Pulp & Paper industry Hydrogen peroxide is commonly used to brighten, delignify and control environmental upsets applied as a versatile bleaching agent in chemical pulp bleaching sequences, in mechanical pulp bleaching as the only or as the dominant bleaching chemical as well as in paper recycling with printing ink removal. In chemical pulp mills, hydrogen peroxide can be used to both delignify and brighten. Since it will effectively replace a portion of the chlorine dioxide requirement in a conventional kraft bleach sequence, and it is an excellent option for the bleacher that needs to increase brightness, increase throughput or lower bleaching costs. In mechanical pulp , hydrogen peroxide is the only brightening solution that will provide high brightness gains (>15 brightness points) while preserving yield. In secondary fiber processing, hydrogen peroxide is a versatile brightener. It can be used in the pulper, disperger, or in a traditional tower post-bleach. In paper recycling the removal of printing ink is the most important objective in case the fibers should be reused in the manufacture of printing papers or tissue grades. Brightening and color removal are secondary targets. Fiber brightening is achieved mainly with H 2O 2. A bleaching agent Hydrogen peroxide is used to bleach a wide range of different products like for oils, waxes, fibres and other natural products. The standard approach is the application of H 2O 2 under alkaline conditions. The concentration and the pH regime can differ in a wide range in order to take care of the specific sensitivity of the products to be bleached. Wood veneer, wooden products, straw and grasses are examples for these products. Hair and bristle need specially buffered bleaching conditions to maintain the raw materials quality. Other products are bleached under weak to strong acidic conditions, e. g. sulfuric acid, vegetable oils or animal products like fish oil. Environmental protection Hydrogen peroxide is a proven, cost-effective solution for a variety of water, soil, and toxic air emissions, for the detoxification and color removal of wastewater . Refineries, chemical plants, paper mills, municipalities, soil remediators and many other types of operations use hydrogen peroxide. With it, they treat or control aldehydes, phenols and other aromatic compounds, reduced sulfur compounds, chlorine, cyanides, NOx, SOx, BOD, COD and several other pollutants. Cosmetic industry Hydrogen peroxide has been designed for a variety of cosmetic and pharmaceutical applications. They are used in professional preparations, in topical solutions which help fight germs without staining, in antiseptics and contact lens cleaning solutions. Food Processing Hydrogen peroxide is approved for use in such FDA approved applications as bleaching instant tea, tripe and dietary fiber and as a sanitizer of polymeric food-contact services used in packaging. When used in food applications, hydrogen peroxide dosing is controlled to minimize the amount of residual hydrogen peroxide. However, any remaining residual normally decomposes to oxygen and water in any subsequent processing steps. Chemical industry Hydrogen peroxide and its in-situ derivatives are powerful oxidizing agents that are environmentally attractive, yet capable of oxidizing a wide range of organic compounds. Hydrogen peroxide is widely used in epoxidation and hydroxylation reactions and it is an excellent choice in oxidative cleavage reactions and for oxidizing ketones, aldehydes, alcohols, organic nitrogen and organic sulfur compounds. Hydrogen peroxide can also be used in a variety of solvent systems since it is soluble in water, many organic solvents or the substrate itself. A method of producing propylene oxide from hydrogen peroxide has been developed. The process is claimed to be environmentally friendly since the only significant byproduct is water. It is also claimed the process has significantly lower investment and operating costs. Two of these “HPPO” (hydrogen peroxide to propylene oxide) plants came onstream in 2008: One of them located in Belgium is a Solvay, Dow-BASF joint venture, and the other in Korea, is a EvonikHeadwaters, SK Chemicals joint venture. A caprolactam application for hydrogen peroxide has been commercialized. Potential routes to phenol and epichlorohydrin utilizing hydrogen peroxide have been postulated.
Hydrogen peroxide is available in various standard grades and specialty grades, differentiated by the stabilizer packages appropriate for the specific end use. As f or commercial use several concentrations ranging from 27 – 90 %, usually 35%, 50% and 70%. (Details) General ranking of H2O2 grades as follows:
|Hydrogen Peroxide 35 %||H2O2 35%|
|Hydrogen Peroxide 50 %||H2O2 50%|
|Hydrogen Peroxide 60 %||H2O2 60%|
|Hydrogen Peroxide 70 %||H2O2 70%|
- 3.5% Pharmaceutical Grade
This is the grade sold at your local drugstore or supermarket. This product is not recommended for internal use. It contains an assortment of stabilizers which shouldn’t be ingested. Various stabilizers include: acetanilide, phenol, and sodium stanate and tertrasodium phosphate.
- 6% Beautician Grade
This is used in beauty shops to color hair and is not recommended for internal use. Must have activator added to be used as a bleach.
- 30% Reagent Grade
This is used for various scientific experiments or medical research and also contains stabilizers. It is also not for internal use.
- 30% to 32% Electronic Grade
This is used to clean electronic parts and not for internal use. Contains a small amount of phosphorus to neutralize any chlorine in the water it is combined with.
- 35% Technical Grade.
This is a more concentrated product than the Reagent Grade and differs slightly in that phosphorus is added to help neutralize any chlorine from the water used to dilute it.
- 35% Food Grade
This is used in the production of foods like cheese, eggs, and whey-containing products. It is also sprayed on the foil lining of aseptic packages containing fruit juices and milk products. This is only grade recommended for internal use. It is available in pints, quarts, gallons or even drums.
- 90% Hydrogen Peroxide.
This is used as an oxygen source for rocket fuel by the military as a source of Oxygen at Cape Canaveral
- 99.5% Hydrogen Peroxide.
This was first made in 1954 as an experiment to see how pure a hydrogen peroxide could be.