Butanone is an important component of the distillate (dry alcohol) of dry-dried wood. Industrially made from sec-butanol, butane, etc.
(1) dehydrogenation of sec-butanol
There are two methods of gas and liquid dehydrogenation. The gas phase dehydrogenation is performed using a zinc-copper alloy or zinc oxide as a catalyst at a temperature of 400-500°C at normal pressure, and the liquid phase dehydrogenation is conducted with Raney nickel or copper chromite as a catalyst at a temperature of 150°C. The liquid phase dehydrogenation reaction has lower temperature, lower energy consumption, higher yield, long catalyst life, and simple separation process.
(2) butane liquid phase oxidation
The main product of butane liquid-phase oxidation is acetic acid, while the by-product butanone (about 16% of acetic acid production). The reaction temperature is 150 to 225°C and the pressure is 4.0 to 8.0 MPa. For example, U.S. Union Carbide Corporation used this method to produce 226 thousand tons of acetic acid in 1976, and obtained 36,000 tons of by-product butanone. About 20% of methyl ethyl ketone is currently produced in the United States using this method.
At present, methods of research and development include liquid-phase oxidation of butene, isobutylene, and the like.
(3) butene liquid phase oxidation
This method is called the Wacker method. The reaction was carried out at 90 to 120C and 1.0 to 2.0 MPa using palladium chloride/cupric chloride solution as a catalyst.
CH2=CHCH2CH3[O2]→CH3COCH2CH3
The conversion of butene was about 95%, the yield of butanone was about 88%, and the obtained reaction solution was purified by distillation or the like to obtain a finished product. This process is simple, but the equipment is heavily corroded and heavy metals are required as catalysts. This method has not yet been applied to large-scale production.
(4) Isobutylene method
n-Butylbenzene is formed from the alkylation of n-butene and benzene, and isobutylbenzene is generated from the oxidation of isobutylbenzene. Finally, butanone and phenol are decomposed with acid.
Alkylation of aluminum trichloride as a catalyst, the reaction temperature of 50 ~ 70 ° C, isobutyl benzene; isobutyl benzene at 110 ~ 130 °C, 0.1 ~ 0.49MPa pressure, liquid phase oxidation to produce isobutyl benzene Hydrogen oxide; then decomposition in the presence of acid catalyst, concentrated at 20 ~ 60 °C oxidation solution, the generation of butanone and phenol, the final separation and purification derived products.
This method is characterized by light corrosion of process equipment, mild reaction conditions, and is conducive to industrialization.