Louis Jacque Thenard discovered hydrogen peroxide in 1818. Each hydrogen peroxide molecule (H2O2) contains two bonded oxygen atoms, each with one hydroge molecule) attached (H-O-O-H). Due to intermolecular repulsion, H2O2 molecules have a skew-chain structure.
The property of hydrogen peroxide deemed most remarkable is that it readily decomposes into water and oxygen, and therefore poses absolutely no threat to the environment. The only safety issue associated with H2O2 is that it can cause skin blistering and is combustible with some substances - but only at high concentrations. H2O2 is soluble in water (regardless of concentration), alcohol and ether. It is not, however, soluble in hydrocarbons. Solutions of hydrogen peroxide are clear, colouriess and have a mildly piquant or acidic odor. Their viscosity and dielectric constant are almost the same as for water, but they have a greater density.
Hydrogen peroxide has been commercially available since the 1800's when it was used primarily for bleaching straw hats. Since that time, production has grown to over one billion pounds annually (as 100% concentration), and its uses now span from food processing to energy production in space crafts. Examples of end-use industries include pulp and paper, electronics, municipal waste water, oil refining, mining, textiles, composting, power production and machining. It is also used in cosmetic, medical, and military applications.
One of the most common uses for hydrogen peroxide is the bleaching of materials such as cotton, feathers, straw, silk, plus other synthetic and natural fibers. It is also used to bleach ground wood pulp and paper - even hair and bones. Furthermore, H2O2 is widely used medicinally as an antiseptic to treat bedsores, broken blisters, animal bite wounds, sore throats, cuts and abrasions, and is readily available in pharmacies (3% concentration).
Hydrogen peroxide's bactericidal and sporicidal properties have made it a useful tool in the food processing industry for equipment and packaging in aseptic systems. H2O2 can also be considered bactericidal at low concentrations (up to 35%). Elevated solution temperatures make it more effective.
Hydrogen peroxide is one of the most potent oxidizers - more powerful than potassium permanganate, chlorine, or chlorine dioxide. It can be catalyzed into hydroxyl radicals which are extremely reactive - indeed only fluorine is more reactive. It is also an extremely versatile oxidizer. It can either inhibit or stimulate microbial growth, oxidize one pollutant above another, and is capable of oxidizing pollutants which require little effort as well as those which are quite problematic.
Hydrogen peroxide has a limited yet extremely important application in energy production. Since it was first used as a propellant to fly an aircraft over fifty years ago, it has been utilized in missiles, torpedoes, submarines, rockets and the Mercury spacecraft. Energy-releasing H2O2 technologies tend to be more efficient, less costly and to weigh less, thus they are useful in a multitude of applications. Research is now being done regarding possible military applications in areas such as electrical power generation.
Hydrogen peroxide is used in the formation of many useful compounds. Caro's acid (used in mining industries), sodium percarbonate (used as an alternative to bleach), Peracetic acid (used for disinfection, sterilization, and as an epoxidizing agent) are examples of such compounds.
Equilibrium producing Caro's Acid
Reaction producing peroxyacetic acid
There seems to be no limit to the number of applications for which hydrogen peroxide can be used, nor to the number of substances produced from H2O2 reactions. Research into future uses is increasing, established applications are expanding. Safe, clean and highly effective, H2O2 is a necessity in today's environment. Continuing to produce hazardous waste and simply transferring contaminants from one location or medium to another will be disastrous. H2O2 can both reduce the amount of waste produced and help repair some of the damage already done. From our homes to rockets in space, hydrogen peroxide is an important and integral part of our lives and of society as a whole.
References
Return to the Gallery.
Return to the Home Page.
End of file.