How to Prepare Acetone in the Laboratory: Experimental Methods and Steps

Acetone (Acetone) is an important organic solvent, which is widely used in chemical, pharmaceutical, cosmetics and other industries. The need to prepare acetone in the laboratory is more common, so "how to prepare acetone in the laboratory"? This article will introduce in detail several commonly used methods for preparing acetone in the laboratory, as well as the principles, experimental steps and precautions of each method.

1. Common acetone preparation methods

Several common methods for the preparation of acetone in the laboratory include the oxidation of alcohols, chemical reduction and hydrogenation of propylene. These methods have their own characteristics and are suitable for different experimental needs. We will introduce a common laboratory method for preparing acetone-the oxidation reaction of isophorone.

2. Preparation of acetone by isophorone oxidation method

experimental principle

Isoborone (isopropanol) is one of the common oxygen-containing organic compounds, which can be converted to acetone under oxidizing conditions. This reaction usually requires a certain catalyst and an oxidizing agent, and the hydrogen atoms in isophorone are oxidized to water by an oxidation reaction to form acetone.

Experimental steps

1. Preparation: Take a certain amount of isophorone (e. g. 100mL) and an oxidizing agent, such as hydrogen peroxide solution.
2. Reaction condition setting: The reactants were put into a reactor, the reaction temperature was adjusted to 70°C, and under aeration conditions, a catalyst (such as copper powder or cobalt salt) was added.
3. Reaction: During the reaction, a constant temperature was maintained, and when appropriate, fractional distillation was performed to collect the acetone fraction.
4. Purification and collection: by simple distillation method to purify acetone, remove water and unreacted isophorone, get pure acetone.

Precautions

When carrying out this reaction, attention should be paid to the control of temperature to avoid excessive temperature leading to side reactions. The choice of oxidant and catalyst will also affect the reaction efficiency, so the appropriate reagent should be selected according to the actual needs.

3. From propylene by hydrogenation to acetone

experimental principle

Propylene (C3H6) is an olefinic compound that can be hydrogenated to produce isophorone and then converted to acetone through further oxidation. This method is suitable for laboratories requiring large yields of acetone.

Experimental steps

1. Propylene preparation: in the experiment need to use high purity propylene, and its hydrogen and catalyst reaction.
2. Hydrogenation: the use of appropriate catalyst (such as nickel or platinum catalyst), at a certain temperature and pressure plus hydrogenation reaction.
3. Fractionation and purification: plus hydrogenation of isophorone by fractional distillation into acetone, and finally purified.

Precautions

This method is suitable for large-scale acetone preparation, but the laboratory scale operation needs to pay attention to the choice of equipment and hydrogen treatment.

4. Preparation of acetone from acetaldehyde by dehydrogenation reaction

experimental principle

Acetaldehyde (Acetaldehyde) can be dehydrogenated to produce acetone, which is a simple laboratory synthesis route. This reaction usually uses a metal oxide as a catalyst to obtain acetone by removing hydrogen from an acetaldehyde molecule.

Experimental steps

1. Raw material preparation: take appropriate amount of acetaldehyde.
2. Reaction Conditions: Acetaldehyde is mixed with a catalyst (e. g. copper oxide) and heated to an appropriate temperature.
3. Reaction: During the reaction, the hydrogen in the acetaldehyde molecule is removed to form acetone.
4. Purification: by fractional distillation separation of acetone and by-products.

Precautions

The use of catalyst and temperature control for this reaction are critical, and appropriate temperature and atmosphere should be ensured to increase the yield.

5. Summary and recommendations

How to prepare acetone in the laboratory? As can be seen from the above methods, there are many ways to prepare acetone in the laboratory, and each method has unique advantages and limitations. For small-scale laboratory preparation, isophorone oxidation is a relatively simple and easy-to-operate method; for experiments requiring large-scale production, propylene hydrogenation can be considered. The choice of each method should be based on laboratory equipment conditions, raw material costs and the purity of the required acetone.

No matter which method is chosen, it is necessary to ensure the safety of the reaction process, and strictly control the reaction temperature and the amount of reagents to avoid dangerous reactions. The purification process is also a key step to ensure the quality of acetone, and both fractionation and extraction techniques can be used to improve the purity of acetone.

It is hoped that this paper can answer the question of "how to prepare acetone in the laboratory" and provide reference and help for the preparation of acetone in the laboratory.