Preparation of ethyl acetate

On the afternoon of December 26th, under the leadership of Mr. Jin Jing in the environmental monitoring craftsman class, we learned about the preparation of ethyl acetate. Before we had no foundation in synthesis, and we didn't even know the basic commonly used instruments. Through this experiment, we not only knew the commonly used instruments for synthesis, but also mastered distillation, liquid separation, drying and other operations.

Experimental steps

01 solution preparation

First, we need to prepare a saturated solution of sodium chloride, calcium chloride, sodium carbonate, etc., and add the corresponding reagents to the beaker until it cannot be dissolved. Seemingly simple solution preparation, due to inexperience, we spent a long time to prepare.

02 Installation Construction

Secondly, we need to set up the device, follow the rules from left to right and from bottom to top. After setting up, do a good job of picking up leaks, first boil the cooling water and then heat it.

03 The reaction proceeds

Furthermore, we need to add ethanol and concentrated sulfuric acid in the three-necked flask. Add ethanol and glacial acetic acid in another beaker, mix the two evenly, and then pour into the long-necked drop funnel. Then boil the cooling water, and then heat the three-necked flask. When the temperature of the mixture reaches 110-120 ° C, start adding the mixture of ethanol and glacial acetic acid dropwise (first add about 5ml at one time), and keep the temperature of the reaction mixture between 115-120 ° C. Until no liquid flows out, collect and retain the coarse product.

04 Refining of ethyl acetate

Next is the refining of ethyl acetate, which requires three steps: washing, drying, and distillation.

• Washing: Add saturated sodium carbonate to adjust the pH until it is not acidic, then pour the mixture into the separation funnel, separate the lye, and wash with an equal volume of saturated salt water. Release the lower salt solution, and then wash the ester layer twice with an equal volume of saturated calcium chloride solution.
• Drying: Add anhydrous magnesium sulfate to crude ethyl acetate to dry, add a stopper, shake well until the liquid is clear and transparent, leave for another 30 minutes to dry.
• Distillation: The dried ethyl acetate is filtered through a funnel through absorbent cotton into a dry distillation flask, a magnetic stirrer is added, a rectifier is set up, heated for distillation, and the fraction at 72-80 ° C is collected and weighed.

Through this experiment, I learned the preparation method of ethyl acetate, deepened my understanding of the esterification reaction, and mastered the basic operation of the experiment, mastered the principle and method of product separation and purification, and learned to control the reaction conditions to improve the yield. Chemistry is not mysterious, it comes from life, but it is higher than life. As long as you observe carefully, life is full of surprises brought to you by chemistry.

- Environmental Monitoring Craftsman Class