Dehydrogenation of (1) sec-butanol
There are two methods of gas phase and liquid phase dehydrogenation. Adopting zinc-copper alloy or zinc oxide as catalyst, and carrying out gas phase dehydrogenation reaction at 400-500 DEG C and normal pressure; Raney nickel or copper chromite is used as catalyst for liquid phase dehydrogenation, and the temperature is 65438 050℃. The liquid phase dehydrogenation reaction has low temperature, low energy consumption, high yield, long catalyst life and simple separation process.
(2) Butane liquid phase oxidation method
Acetic acid is the main product of liquid phase oxidation of butane, and butanone (about 16% of acetic acid output) is also produced. The reaction temperature is 150 ~ 225℃ and the pressure is 4.0 ~ 8.0 MPa. For example, Union Carbide Company of the United States produced 226,000 tons of acetic acid by this method in 1976, and obtained 36,000 tons of by-product butanone. At present, about 20% of butanone in the United States is produced by this method.
At present, the methods being studied and developed include liquid phase oxidation of butene and isobutyl benzene.
(3) Liquid phase oxidation of butene
This method is called the Wacker method. Using palladium chloride/copper chloride solution as catalyst, the reaction was carried out at 90 ~ 120℃ and 1.0 ~ 2.0 MPa.
CH2=CHCH2CH3[O2]→CH3COCH2CH3
The conversion of butene is about 95%, and the yield of butanone is about 88%. The obtained reaction solution is purified by distillation and other methods to obtain the finished product. This process is simple, but the equipment is seriously corroded, and heavy metals are needed as catalysts. This method has not been applied to mass production.
(4) isobutyl benzene process
Butene and benzene are alkylated to produce isobutyl benzene, which is oxidized by hydrogen peroxide to produce isobutyl benzene. Finally, butanone and phenol were obtained by acid decomposition.
Benzene alkylation takes aluminum trichloride as catalyst, and the reaction temperature is 50 ~ 70℃ to obtain isobutyl benzene; Isobutylbenzene was oxidized in liquid phase at 1 10 ~ 130℃ and 0. 1 ~ 0.49 MPa to produce isobutyl benzene hydrogen peroxide. Then decompose in that presence of an acidic catalyst, concentrating the oxidation solution at 20-60 DEG C to generate butanone and phenol, and finally separate and refining to obtain a finished product.
This method is characterized by mild corrosion of process equipment and mild reaction conditions, which is beneficial to industrialization. Butanone is an important component of wood dry distillation distillate (wood alcohol oil). It is industrially prepared from sec-butyl alcohol and butane. 1. The mixed C4 fraction containing butanol contacts with sulfuric acid to generate acid sulfate and China sulfate, which are diluted and hydrolyzed with water to generate sec-butanol aqueous solution, and then dehydrated and concentrated to obtain sec-butanol. Pure sec-butanol is dehydrogenated with nickel oxide or zinc oxide to obtain the finished product. 2. There are two methods for direct hydration of n-butene, one is resin as catalyst, and the other is heteropoly acid as catalyst. 3. Dehydrogenation of sec-butanol This process is divided into gas phase method and liquid phase method, and most of them adopt gas phase dehydrogenation process. That is, sec-butanol is dehydrogenated under the action of dehydrogenation catalyst to prepare butanone. 4. Gas phase oxidation of ethylene. 5. Alkylation of isobutylene and benzene produces isobutylene, which is oxidized by hydrogen peroxide to produce isobutylene, and then decomposed by acid to obtain butanone and phenol. This method is characterized by mild corrosion of process equipment and mild reaction conditions, which is beneficial to industrialization. It is prepared by mixing n-butene and sulfuric acid for hydrolysis, distilling to separate sec-butanol, and then catalytic dehydrogenation.
It is formed by direct oxidation of butane.