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ChemicalBook CAS DataBase List Sodium methylparaben
5026-62-0

Sodium methylparaben synthesis

2synthesis methods
-

Yield:-

Reaction Conditions:

in water;

Steps:

1 EXAMPLE 1

EXAMPLE 1 873.3 g of methyl 4-hydroxybenzoate were suspended in 2,000 ml of water and neutralised at 20° C. with 301 ml of 50% strength sodium hydroxide solution, the sodium hydroxide solution, towards the end of the addition, being metered in slowly at a rate such that the pH value of 12.1 established after complete neutralisation was never exceeded. Half of the solution thus obtained, after about 90 minutes, was dried immediately in a spray-drier at an air inlet temperature of 220° C. and an air outlet temperature of 130° C. (a). The second half of the solution was passed to the spray-drier after being kept at a temperature of 20° C. for 92 hours (b). The sodium salt of methyl 4-hydroxybenzoate is obtained with a 4-hydroxybenzoic acid content of 0.4% by weight and a water content of 1.3% by weight in case (a) and with a 4-hydroxybenzoic acid content of 2.5% by weight and a water content of 4.2% by weight in case (b).

References:

US4276431,1981,A

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