Selection of raw materials for the synthesis of triacetin
To make triacetin, suitable raw materials need to be prepared. Glycerol and acetic acid are usually selected as the starting materials. Glycerol has trihydroxyl groups and can be esterified with acetic acid. The two sources are wide and the cost is relatively suitable. They are commonly used raw materials for synthesis.

Reaction process
An appropriate amount of glycerol and acetic acid are placed in a reaction vessel in a certain proportion, and concentrated sulfuric acid is often used as a catalyst, because it can effectively promote the esterification reaction. The reaction vessel needs to have good sealing and heat resistance to ensure that the reaction occurs under suitable conditions.

Heat the reaction system to maintain a certain temperature range, generally between 100 and 130 ° C. At this temperature, the hydroxyl group of glycerol and the carboxyl group of acetic acid undergo esterification reaction, and gradually form triacetin and water. During the reaction process, it is necessary to continuously stir to make the reactants fully contact, accelerate the reaction process, and at the same time uniformly heat to avoid local overheating or uneven reaction.

Separation and purification
After the reaction is completed, in addition to triacetin, the product still contains impurities such as unreacted raw materials, catalysts, and generated water, which need to be separated and purified. First, the method of distillation can be used. Due to the different boiling points of triacetin and other ingredients, triacetin can be distilled from the reaction mixture by controlling the temperature, and most of the impurities are initially separated.

Next, the alkali washing step is used to wash the distilled product with a weak base such as sodium carbonate solution, neutralize the residual sulfuric acid catalyst, and remove some acidic impurities. Then it is washed with water to remove the residual alkali and water-soluble impurities. Finally, the product is dried with a desiccant such as anhydrous magnesium sulfate to remove the residual moisture, thereby obtaining pure triacetin.