Views: 282 Author: Vickey Publish Time: 2023-04-24 Origin: Site
Ethylene glycol is also known as glycol, 1,2-ethyleneglycol, or 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 raw material for synthetic polyester. Polyethylene glycol (PEG) is a phase transfer catalyst also used for cell fusion; its nitrate is an explosive.
Ethylene glycol is mainly used in making polyester, polyester resin, hygroscopic agent, plasticizer, surfactant, synthetic fiber, cosmetics, and explosives. It is also used as dyes, ink solvent, preparation of engine antifreeze, gas dewatering agent, and manufacturing resin. It can also be used in cellophane, fiber, leather, and adhesive wetting agents. Can produce synthetic resin PET, fiber grade PET, namely polyester fiber, bottle sheet grade PET, which is used for making mineral water bottles, etc. can also produce alkyd resin, glyoxal, and so on, but is also used as antifreeze. In addition to being used for automotive antifreeze but also for the transportation of industrial cooling, generally known as the cooling agent, water can also be used as a condensate.
Ethylene glycol methyl ether series products are advanced organic solvents with excellent performance as solvents and thinners for printing ink, industrial cleaning agents, paint (nitrofiber paint, varnish, porcelain paint), copper coating plates, printing, and dyeing. They can also be used as raw materials for chemical products such as pesticide intermediates, pharmaceutical intermediates, synthetic brake fluid, electrolytes for electrolytic capacitors, leather chemical fiber dye, etc. It is used as textile additives, synthetic liquid dyes, fertilizer, and desulfurizer in oil refining production.
Ethylene glycol can be made using the following methods:
Chloroethanol was obtained by hydrolysis in an alkaline medium, and the reaction was performed at 100 °C.
2.Ethylene oxide water is legal
Ethylene oxide water is legal for direct water and catalytic water, and the hydration process50–70 °C can also be carried out under normal prGenerally,enerally using a small amount of inorganic acid as the catalyst for the reaction at 50~70℃. Ethylene oxide in direct water is a mature production method for ethylene glycol. Ethylene oxide and water are the direct liquid hydration products of ethylene glycol under pressure (2.23 MPa) and 190–200 °C in a tubular reactor, with the byproducts monoshrink diethylene glycol, dishrink triethylene glycol, and polyshrink polyethylene glycol.
Direct water is legal;
Catalytic water is legal;
Pressurized water is legal: the molar ratio of ethylene oxide to water is higher, above 1 6, to reduce the side reaction of ether formation, the temperature of the reaction is 150 °C, and the pressure is 147 kPa. Hydrated to ethylene glycol.
3.Gas catalytic water
silver oxide as the catalyst, alumina as the carrier, in a 150–240 °C reaction to form ethylene glycol
4.Ethylene direct water legal
ethylene in the presence of catalyst (such as antimony oxide TeO2, palladium catalyst) in acetic acid solution oxidation to produce monoloacetate or diacetate, further hydrolysis of ethylene glycol.
5.Ethylene oxide and water are rehydrated under the action of a sulfuric acid catalyst, and the reaction solution is obtained by alkali neutralization, evaporation, and distillation. Or ethylene oxide and water at a certain temperature and pressure to make ethylene glycol, with the addition of diethylene glycol, triethylene glycol, and polyethylene glycol. The reaction solution is evaporated, concentrated, dehydrated, and refined to obtain qualified products and by-products.
7.Intermediate fractions were collected at 1333Pa.
8.Ethylene glycol was distilled under vacuum, and the main fractions were dried with anhydrous sodium sulfate for a long time and then re-vacuum distilled with a good fractionation column.