Sodium diacetate Usage and Synthesis

Sodium diacetate Usage and Synthesis

Chemical properties: 

White crystals. With acetic acid odor. Easy to absorb moisture. Very soluble in water (1g/m1), releasing 42.25% acetic acid. Ph value of 10% aqueous solution is 4.5-5.0. Decomposed on Chemicalbook when heated to 150℃. Flammable. Has strong inhibitory effect on spores and molds of heat-resistant bacteria Bacillus mesentericus and Bacillus subtilis.

Uses: 

Preservative; Antifungal agent; Acidity regulator: Chelating agent.

As a preservative, my country stipulates that it can be used in cereals and ready-to-eat soy foods, with a maximum usage of 1g/kg. It can also be used as a feed additive and chelating agent.

Sodium diacetate is a multifunctional edible chemical. It is mainly used as a preservative, mildew preventer, chelating agent, flavoring agent, pH regulator, meat product preservative in the food and feed industry, and is also the main ingredient of compound mildew preventer.

Production method:

Reaction of acetic acid and sodium carbonate: 

Add 5.3g (0.05mol) of sodium carbonate and 2mL of water to the reaction bottle, stir and heat to 40℃, then slowly add 12.0g (0.Chemicalbook2mol) of glacial acetic acid. After the addition, react at 80℃ for 4h, cool and crystallize, filter; concentrate the filtrate and crystallize, combine the two white crystals, and dry to obtain 13.6g of the product, with a yield of 95.8%.

Reaction of acetic acid and acetic anhydride with sodium carbonate: 

Add 9.2g of sodium carbonate to 8.4ml of acetic anhydride, and add 13mL of acetic acid in batches after uniform wetting. After stirring for a certain period of time, stand and dry to obtain 24.6g of product. Alternatively, 5.3g (0.05mol) of sodium carbonate and 3mL of water can be added to the reaction bottle, stirred and mixed, and the temperature is raised to 40%, and 6.0g (0.1mol) of glacial acetic acid and 5.1g (0.05mol) of acetic anhydride are added alternately. After the addition is completed, the reaction is continued at 70℃ for 3h. Cool to room temperature, filter the crystals, concentrate the filtrate and recrystallize. Combine the two crystals and dry to obtain 13.7g of product with a yield of 96.5%.

Gas phase reaction of acetic acid and sodium acetate: 

Sodium acetate and acetic acid are reacted in a fluidized bed reactor at 20-200°C according to stoichiometric ratios using nitrogen or carbon tetrachloride as the flowing medium to produce sodium diacetate. This method has a large production capacity, but the conditions are strictly controlled and the acid in the waste gas must be recovered.

Acetic acid reacts with sodium acetate in 45% ethanol: 

8.2g (0.1mol) sodium acetate is added to 5mL 50% ethanol. After stirring evenly, heat to 60℃, start to drop 6.0g (0.1mol) Chemicalbook sodium acetate, continue stirring and reacting at 60-80℃ for 4h. Then cool to room temperature, stand for crystallization, filter to obtain white crystals, concentrate the filtrate, recrystallize, and dry to obtain 13.3g sodium diacetate, with a yield of 93.7%.