Ethylene glycol (HOCH₂CH₂OH) is a colorless syrupy liquid. It can harm the eyes, skin, kidneys, and respiratory system. Swallowing ethylene glycol can cause death. Workers may be harmed by exposure to ethylene glycol. The degree of exposure depends on the dose, duration, and the job being done.

Glycol is used in many industries. It is used as an antifreeze, in the manufacture of polyester plastics, and in some manufacturing.

Basic information

Ethylene glycol

also known as glycol, 1,2-ethyleneglycol, EG. The chemical formula, (CH2OH) 2, is the simplest binary alcohol. Ethylene glycol is a colorless, odorless, sweet liquid with low toxicity to animals. Ethylene glycol can interdissolve with water and acetone, but it has less solubility in ethers. Used as a solvent, antifreeze, and a raw material for synthetic polyester. High glycol polyethylene glycol (PEG) is a phase transfer catalyst also used for cell fusion; its nitrate is an explosive.

Physical property

Steam pressure: 0.06 mmHg (20℃)

Viscosity: 25.66 mPa.s (16℃)

Heat of combustion: 1180.26 kJ / mol

Spontaneous combustion point: 418℃

critical temperatures:372℃

Critical pressure: 7,699 kPa

Critical molar volume: 186C3 / mol

Eccentricity factor: 0.27

Surface tension: 46.49 m N/m (20℃)'

Solubility: miscible with water / ethanol / acetone / pyridine acetate, slightly soluble in ether, insoluble in petroleum hydrocarbons and oils, can dissolve calcium chloride / zinc chloride / sodium chloride / potassium carbonate / potassium chloride / potassium iodide / potassium hydroxide and other inorganic substances.

At 25 degrees C, the dielectric constant is 37.

It is easy to absorb moisture at high concentration.

Chemical property

Because of the low molecular weight, active nature, it can be esterification, etherification, alcoholization, oxidation, acetal, dehydration and other reactions.

Similar to ethanol, it can mainly react with inorganic or organic acids to produce esters. Generally, only one hydroxyl group reacts first. After increasing the temperature and increasing the amount of acid, both hydroxyl groups can form esters. If reacted with the nitric acid mixed with sulfuric acid, the dinitrate is formed. Acyl chloride or anhydride readily causes two hydroxyl groups to form esters. When ethylene glycol is heated under the action of catalyst (manganese dioxide, alumina, zinc oxide, or sulfuric acid), intra-molecular or intermolecular water loss may occur. Ethylene glycol can interact with alkali metals or alkali soil metals to form alcohol salts. When the metal is usually dissolved in the diol, only a single alcohol salt; if the alcohol salt (such as ethylene glycol monosodium) is heated in the hydrogen flow to 180~200 C, ethylene glycol disodium and ethylene glycol can be formed. In addition, use ethylene glycol with 2mol sodium methanol to obtain ethylene glycol diodium. Didium glycol reacts with halogenanes to produce ethylene glycol monoether or double ether. Disodium ethylene glycol reacts with 1,2-dibromoethane to form a dioxygen ring. In addition, ethylene glycol is also easy to oxidation, with the different oxidant or reaction conditions used, can produce various products, such as glycolaldehyde HOCH2CHO, glyoxal OHCCHO, glycolic acid HOCH2COOH, oxalate HOOCCOOH and carbon dioxide and water. Ethylene glycol, unlike other diols, can undergo carbon chain breakage upon periodate oxidation. Ethylene glycol is often used instead of glycerol. In the tanning and pharmaceutical industries, used as hydration and solvents, respectively. Dinitrate, a derivative of ethylene glycol, is an explosive. Single ether or single ether of ethylene glycol are good solvents, such as HOCH2CH2OCH3, a fiber-soluble fibers, resins, paints, and many other organic matter. Ethylene glycol has a strong dissolution capacity, but it is easy to metabolism and oxidation to produce toxic oxalic acid, so it cannot be widely used as a solvent.

Application

It is mainly used for making polyester, polyester, polyester resin, hygroscopic agent, hygroscopic agent, plasticizer, surfactant, synthetic fiber, cosmetics and explosives, and used as dyes, ink and other solvents, preparation of engine antifreeze, gas dewatering agent, manufacturing resin, can also be used in cellophane, fiber, leather, adhesive wetting agent. Can produce synthetic resin PET, fiber grade PET, namely polyester fiber, bottle sheet grade PET is used for making mineral water bottles, etc. Also can produce alkyd resin, glyoxal, and so on, but also used as antifreeze. In addition to being used as an antifreeze agent for automobiles, it is also used for the transportation of industrial cooling capacity, generally known as the carrier cooling agent, and at the same time, it can also be used as water as a condensate agent.

Ethylene glycol methyl ether series products are advanced organic solvents with excellent performance, used as solvent and thinner for printing ink, industrial cleaning agent, paint (nitrofiber paint, varnish, porcelain paint), copper coating plate, printing and dyeing; can be used as raw materials for chemical products such as pesticide intermediates, pharmaceutical intermediates and synthetic brake fluid; as electrolyte for electrolytic capacitor, leather chemical fiber dye, etc. It is used as textile additives, synthetic liquid dyes, as well as fertilizer and desulfurizer in oil refining production