What Is Ethylenediamine?
Ethylenediamine is a type of primary diamine, a clear liquid at room temperature with an ammonia odor. It is also known as 1,2-diaminoethane, 1,2-ethanediamine, and dimethylenediamine.
It is mainly used as a raw material for making other chemicals.
Uses of Ethylenediamine
Ethylenediamine is used as a synthetic raw material to make new chemicals because of its high reactivity with many compounds.
Examples in industrial fields include synthetic waxes, herbicides, surfactants, emulsifiers, wetting agents, dispersants, corrosion inhibitors, detergents, and textile surface treatments.
Examples in the medical field include drug synthesis as chemical stabilizers, such as antihistamines, and a wide range of applications, such as allergic epithelial patch testing to aid in the diagnosis of allergic dermatitis.
In the agrochemical field, it is also used in fungicides, insecticides, and herbicides.
Other applications include chelating agents, coatings, adhesives, ion exchange resin raw materials, and rubber chemicals.
Properties of Ethylenediamine
The chemical formula of ethylenediamine is NH2CH2CH2NH2, with one hydrogen atom attached to each of the two carbons of ethylene being replaced by an amine group. It has a molecular weight of 60.11, a density of 0.9 g/cc, a melting point of 8.5°C, a boiling point of 117°C, and is freely miscible with water and alcohols but slightly soluble in ether.
It is a strong base and will corrode attached tissues. When heated, it produces toxic fumes of nitrogen oxides and ammonia, so it should be handled with care.
Ethylenediamine has an unpleasant ammonia odor and can cause pain and irritation to the eyes, nose, throat, and respiratory system, and in rare cases can be life threatening.
In case of contact with eyes or skin, it is important to flush with plenty of water, seek medical attention, and move to fresh air if concentrated vapors are inhaled.
Other Information on Ethylenediamine
1. How Ethylenediamine Is Produced
Ethylenediamine is produced by the reaction of ethylene dichloride with ammonia or ammonia water. These raw materials are mixed and heated under pressure at 110°C to react.
ClCH2CH2Cl + 2NH3 / NH2H2CH2NH2 + 2HCl
The product obtained from the reaction is sent to a distillation column. There, unreacted ethylene dichloride is separated and returned to the reaction tank. In the distillation column, 40% caustic soda is shaken to neutralize the generated amine hydrochloride and ammonia chloride, and the excess ammonia that is released is returned to the reaction column for reuse.
Ethylenediamine and brine recovered from the bottom of the distillation column are sent to a separation tank, where the brine is separated from the ethylenediamine. It is purified in the rectifying column at atmospheric pressure and at 150~180℃. The residues are ethylenediamine and polyamine with boiling points of 200°C or higher. The ratio of ethylenediamine to polyamine above triamine is 2:1.
2. Polymers of Ethylenediamine
Like ethyleneglycol, ethylenediamine exists in polymers (polyethyleneamines) such as dimers and trimers. These are also produced in the manufacturing process of ethylenediamine and are separated in the distillation process. They are represented by the general formula NH2-(CH2-CH2NH)n-H and include diethylenetriamine, triethylenetetetramine, tetraethylenepentamine, and pentaethylenehexamine.