The physicochemical properties and preparation method of glutaraldehyde

Glutaraldehyde

[Structural formula]

[Physical and chemical properties] Colorless or light yellow oily liquid

[Preparation]

(1) Cyclopentene oxidation method

Cyclopentene oxidation is the earliest method used to synthesize glutaraldehyde.

(2) Pyridine method

This method uses pyridine as raw material, reduces pyridine to dihydropyridine with methanol and sodium metal , and then treats with hydroxylamine hydrochloride to obtain glutaraldehyde .

The conversion rate of this method can reach 90%, but the yield is low, about 50%

(3) Pyran method

In 1950, Lonely and Emerson used acrolein and ethyl vinyl ether as raw materials to synthesize glutaraldehyde through a two-step reaction of addition hydrolysis

The first step reaction produces 2-ethoxy-3,4-dihydropyran

The second step is the hydrolysis reaction.

(4) Polyol oxidation method

In the early days, some people used lead tetraacetate to oxidize and decompose 1,2-cyclopentanediol or 1,2,3-cyclohexanetriol to synthesize glutaraldehyde, but cyclopentanediol is still made from cyclopentene

(5) Glutaric acid method

In industry, a large amount of glutaric acid is by-produced in the process of producing adipic acid.