EDTA, full name ethylene diamine tetraacetic ACID, is an organic compound, odorless and tasteless, melting point 250 ℃ (decomposition), white powder under normal temperature and pressure, soluble in sodium hydroxide, sodium carbonate and ammonia solution, soluble in boiling water, slightly soluble in cold water, insoluble alcohol and general organic solvent. It is a chelating agent that can combine with divalent metal ions such as Mg2+, Ca2+, Mn2+and Fe2+. Because most nucleases and some proteases require Mg2+, they are often used as inhibitors of nucleases and proteases; It can also be used to remove the inhibition of heavy metal ions on enzymes.
EDTA is an important complexing agent. EDTA has a wide range of uses. It can be used as bleaching fixer, dyeing aid, fiber treatment aid, cosmetic additive, blood anticoagulant, Detergent, stabilizer, and synthetic rubber polymerization initiator for the washing and processing of color photosensitive materials. EDTA is the representative material of chelating agent, TA # heavy metal chelating agent #. It can form stable water-soluble complexes with alkali metals, rare earth elements and transition metals. In addition to sodium salt, there are ammonium salt, iron, magnesium, calcium, copper, manganese, zinc, cobalt, aluminum and other salts, which have different uses. In addition, EDTA can also be used to rapidly excrete harmful radioactive metals from the human body to detoxify them. EDTA is also an important indicator, but it is used to titrate metal nickel, copper, etc. When used, it should be used together with ammonia to play the role of indicator.
EDTA is an excellent chelating agent for calcium and magnesium ions. It is used as a chelating agent for water used in lotion polymerization to remove Ca2+, Mg2+, Fe2+, Fe3+and other metal ions. It is also used as the complexing agent of anaerobic adhesive, that is, EDTA is used to treat the diester of methacrylate to remove the transition metal ions and eliminate the influence that can promote the decomposition of peroxide, which has a very good effect on improving the stability of anaerobic adhesive. EDTA sodium salt chelating metal ions can improve the modification speed of acrylic acid. Storage stability of solid structural adhesive (SGA), dosage - 3 × 10-4～6.0 × 10-4。 When the dosage is 1.5%, the storage stability at 50~C can reach more than 360h (4 days at 50 ℃, equivalent to 1 year at SGA20~C).
Application in Water Treatment: EDTA has extensive coordination ability, can form stable chelates with almost all metal ions, and its metal chelates have good solubility in slightly acidic conditions, so it has long been used as an inhibitor of harmful metal ions and a water softener in the textile industry. Because of the good water solubility of its metal ion chelates, more and more research and applications have been made in the cleaning of water equipment.
Application in agriculture: Cu, Ca, Fe, Mg, Zn and other metal salts of EDTA series chelating agents have the advantages of good solubility and easy absorption, and become a good source of microelement fertilizer. Moreover, these chelated metal salts do not affect their solubility after mixing with each other, which is conducive to the use of multi-element compound microelement fertilizer. Moreover, EDTA has carboxyl groups involved in the reaction, which can generate potassium salt, ammonia salt, etc., and supplement potassium fertilizer and nitrogen fertilizer while supplementing trace elements. Considering the cost and effect comprehensively, it will be the first choice of chelated microelement fertilizer for a long time. Therefore, its application in China is becoming more and more extensive.
Applications in other industries: EDTA series chelating agents are also widely used in photography, textile, printing and dyeing, paper making, daily chemical, chemical analysis, etc. The ferric ammonium salt of EDTA can be used as the bleaching fixer for the processing of color sensitive materials. EDTA can Mask metal ions, increase the activity of surfactants and the stability of foam generation, enhance the cleaning power, foaming power, penetration power and emulsifying power of detergents, and help improve cleaning efficiency. Cellulose often contains various metal ions, among which Fe3+ions are difficult to remove. Adding EDTA can effectively remove Fe3+ions. The addition of EDTA in pulp can reduce the decomposition of Hydrogen Peroxide, improve the utilization of hydrogen peroxide and increase the brightness of pulp during pulp bleaching.
Adding EDTA in the process of processing edible oil can remove metal ions, increase the stability of edible oil and prevent its oxidation. The sodium salt of EDTA is used as an additive in shampoo, shower gel and cosmetics to prevent the rancidity caused by metal ions. In addition, EDTA pretreatment of glass surface can improve the brightness of decoration glass. Adding calcium EDTA and aluminum EDTA into the battery can prolong the service life of the battery. As a metal ion complexing agent, Changzhou Shanfeng EDTA is widely used in water treatment, detergent additives, lighting, paper making, oilfield chemicals and other fields. As metal ion chelating agent, EDTA products are widely used in washing, water treatment, color photography, paper making, electronic chemicals and other industries.
