Things You'll Need:
- Distillation apparatus
- Propene
- Sulfuric acid, 90 percent solution
- Reactor capable of 50 atm pressure and 500 degrees C heat
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Step 1
Use sulfuric acid to make isopropyl alcohol through indirect hydration. This is the most common method for preparing isopropyl alcohol in the United States. Its primary advantage is the use of low-quality propylene.
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Step 2
React propene (CH3CH=CH2) with a solution of 88 to 93 percent pure sulfuric acid (H2SO4) in a reaction chamber. The chamber provides the specific conditions of time, pressure and heat. And it yields a mixture of isopropyl sulfate [CH3-CH(OSO3H)-CH3] and diisopropyl sulfate [(CH3)2-CH-(OSO3)-CH-(CH3)2] as follows:
3CH3CH=CH2 + 2H2SO4 -> CH3-CH(OSO3H)-CH3 + (CH3)2-CH-(OSO3)-CH-(CH3)2. -
Step 3
Examine the reaction given in Step 2. This is a general reaction to show the reagents and products. The specific mixture of isopropyl sulfate and diisopropyl sulfate obtained depends on a variety of factors, including the exact proportions of propene and sulfuric acid and the conditions in the reactor.
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Step 4
Add water to the mixture of isopropyl sulfate and diisopropyl sulfate to yield isopropyl alcohol and sulfuric acid. The following equation shows this reaction:
CH3-CH(OSO3H)-CH3 + (CH3)2-CH-(OSO3)-CH-(CH3)2 + 2H20 -> 3CH3-CH(OH)-CH3 + 2H2SO4. -
Step 5
Purify the alcohol obtained in Step 4. Distill the alcohol to separate it from the water and sulfuric acid. This process also must remove the by-products of diisopropyl ether and isopropyl oils.
