ChemicalBook CAS DataBase List Glycolic acid

Glycolic acid synthesis

14synthesis methods

Product Name:Glycolic acid
CAS Number:79-14-1
Molecular formula:C2H4O3
Molecular Weight:76.05

There are different preparation methods to synthesize glycolic acid. However, the most common method is the catalyzed reaction of formaldehyde with synthesis gas, which costs less. It can be prepared when chloroacetic acid reacts with sodium hydroxide and undergoes re-acidification. Electrolytic reduction of oxalic acid also could synthesize this compound. Glycolic acid can be separated from natural sources like sugarcane, sugar beets, pineapple, cantaloupe, and unripe grapes. It can be prepared by hydrolyzing the cyanohydrin that is derived from formaldehyde.

96-35-5 Synthesis

96-35-5
336 suppliers
$5.00/5g

79-14-1
849 suppliers
$6.00/25g

Yield:79-14-1 100%

Reaction Conditions:

with water at 95 - 97; under 760.051 Torr; for 2 h;Reactive distillation;

Steps:

2-1.4 (4) Hydrolysis Reaction (Hydrolysis by Reactive Distillation)

As a reactive distillation apparatus, an apparatus obtained by connecting a 3-stage packed column to a flask and further providing a refluxing device at the top of the packed column was used. A mixed liquid obtained by mixing 150 g of water with 50 g of the distillate containing more than 98 wt % of methyl glycolate obtained in (3) above was put into the flask. Next, reactive distillation was carried out for 2 hours at normal pressure, maintaining the temperature at the base of the column of the reactive distillation apparatus (i.e. the liquid temperature) at 95 to 97° C. At this time, distillate containing methanol was distilled off. The temperature at the top of the column was 65° C. at the start of the reactive distillation, but had reached 100° C. by the end. [0322] After the reactive distillation had been completed, 114 g of an aqueous solution containing 36.1 wt % of glycolic acid was recovered from the flask. The yield of glycolic acid relative to the methyl glycolate was 100%. Regarding impurities, formaldehyde and chlorine compounds were not detected, and 20 ppm of oxalic acid and 76 ppm of ethylene glycol were detected.

References:

US2004/138409,2004,A1 Location in patent:Page 23