Catalase -- Decomposition of Hydrogen Peroxide (H202)

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Methods of Dechlorination

Sulfur Dioxide/Sulfite Salts

L-Ascorbic Acid

Hydrogen Peroxide

Activated Carbon

Industrial Water Pollution and Its Effect on Aquatic Ecosystems: H2O2 as a Dechlorination Alternative

Manufacturing of Detergent Bleaches

clothing bleach

produce sodium perborate and sodium percarbonate (bleaching agents in solid and liquid detergents)

Food Processing Industry

Pasteurization was the traditional method used to eliminate substances including hydrogen peroxide which compromise the taste of a variety of milk products. However, it involved the use of heat; this was problematic as many other enzymes that enhance final flavor of the product were denatured. As a result, catalase is now used in the production process in order to convert hydrogen peroxide into water and oxygen gas without affecting the final product. In addition, hydrogen peroxide prevents the growth of bacterial cultures that are beneficial in the cheese production process. Therefore, it is critical that all traces of hydrogen peroxide be removed.

helps to control viscosity of starch and cellulose derivatives

applied in bleaching, oxidizing and neutralizing (in wine distillation) processes

Aseptic Packaging

antimicrobial agent

long shelf life

Textile Bleaching

allows not only a high degree of brightness, but also preserves the mechanical properties of the fibers

The traditional method to remove excess hydrogen peroxide was to rinse the fabric with water. Approximately 40 liters of water are required to remove hydrogen peroxide from 1 kilogram of fabric, as a result this process is economically and environmentally demanding

Medical

Accumulation of hydrogen peroxide may have very bad influence on cells and can even kill them, so it has to be decomposed

reactions in cells are mostly accelerated by enzymes

Catalase lowers the energy of activation needed for decomposition

can have significant impact on aging processes; during decomposition of hydrogen peroxide with, for example, copper (I) and iron (II) ions as a catalyst, hydroxyl radical (OH●) is formed. Free radicals are molecules, atoms or ions which have single, unpaired electron at the outer orbits. High activity individuals have this chemical and oxidize each compound with which they have contact in order to join or donate electrons. The objects of the attacks of free radicals in the human body are mainly compounds having double bonds in the molecules like proteins, DNA, polysaccharides, lipids (like cholesterol in the blood) or unsaturated fatty acids which are part of cell membranes

Hydrogen peroxide could also be found in exhaled air of living organisms. It is uncertain whether the source of it is oral bacteria, phagocytes or other lung cells. People with lung diseases or cigarette smokers exhale more hydrogen peroxide than healthy ones

Hydrogen peroxide naturally occurs in the human body as one of the by-products of biochemical metabolism of many different cells

High reactivity gives H2O2 the ability to damage cellular macromolecules, including lipids, proteins and nucleic acids

Cosmetics

hair bleach

tooth whitening

The Environment

Hydrogen peroxide is a "green" product with the only by-products being oxygen and water, making it desirable for facilities looking to eliminate chemicals such as bleach and non-oxidizing biocides

exhaust air treatment

Dechlorination

Chlorine continues to be used throughout industry as a bleaching agent, a disinfectant, and an oxidizer. As a result, it is present in many industrial and municipal wastewaters

chlorine residuals, even at very low levels, are toxic to certain fish and other aquatic life

Pulp and Paper Industry

used as a chemical intermediate, in the bleaching and deodorizing processes

ncreases brightness levels, improves brightness stability, and reduces manufacturing cost, as it is the only one chemical that is required

Purification of Water

used in water treatment operations (substitute for chlorine in water and sewage treatment)

Mining

oil and petrochemical refinery

refining and cleaning metals

used as an oxidant in such metallurgical process steps as ore leaching, concentrate preparation or eluent treatment

simplifies management of chemicals or waste and improves the overall process control

Chemical Synthesis

organic chemicals (manufacture of glycerol)

due to its molecular structure, it consists atoms of oxygen in oxidation state of -1 unlike many substances, where oxygen occurs in oxidation state of 0 or -2. This means that this substance can be used as both an oxidizing and a reducing agent, depending of pH of its solution.

It is solvable in several organic solvents including water and the substrate itself

Pharmaceutical

One common contact lens disinfectant includes hydrogen peroxide, which oxidizes and cleans the lens. Since hydrogen peroxide is dangerous to the cells of the body, it must be removed. First contact lenses are placed in a hydrogen peroxide containing solution and then placed into a second container, which contains catalases

Hospitals and other healthcare systems find hydrogen peroxide ideal for sanitizing and disinfecting rooms,