Production of Acetone
5.1 MANUFACTURING PROCESSES:
Acetone is produced directly or indirectly by propylene. Early processes for the manufacture of acetone were based on the thermal decomposition of calcium acetate or the carbohydrate fermentation of corn starch or molasses. The ready availability of propylene in the 1960s led to routes based on the dehydrogenation of isopropyl alcohol or cumene peroxidation.
(1) By Cumene Oxidation (Hock Process).
Propene is added to benzene [71-43-2] to form cumene [98-82-8], which is then oxidized by air to cumene hydroperoxide, and cleaved in the presence of an acid catalyst like zeolite. Phenol [108-95-2] and acetone [67-64-1] produced in the process are recovered by distillation. Ratio of phenol to acetone is 1:0.6.
(2) By Dehydrogenation of 2-proponal
The hydration of propene [115-07-1] gives 2-propanol [67-63-0], which is then dehydrogenated to acetone. In the United States a C3 stream containing 40 – 60 % propene is used for the manufacture of 2-propanol. A large number of catalysts for 2-propanol dehydrogenation have been studied, including copper, zinc, and lead metals, as well as metal oxides, e.g., zinc oxide, copper oxide, chromium-activated copper oxide, manganese oxide, and magnesium oxide. Inert supports, such as pumice, may be used.
CH3CH=CH2 CH3CH(OH)CH3 CH3COCH3 +H2
(3) By catalytic oxidation of Propene (Wacker-Hoechst).
The process is analogous to the oxidation of ethylene to acetaldehyde by theWacker process. The catalyst solution typically contains 0.045M Palladium (II) chloride, 1.8M Copper (II) Chloride, and acetic acid. The reaction usually is carried out in two alternating stages. In the first stage, air is used to oxidize the metal ions to the +2 oxidation state. In the second, air is removed and propene added. Palladium (II) oxidizes propene, and the resulting Palladium (I) is reoxidized by the pool of copper (II). Besides propionaldehyde, chlorinated carbonyl compounds and carbon
Acetone is produced directly or indirectly by propylene. Early processes for the manufacture of acetone were based on the thermal decomposition of calcium acetate or the carbohydrate fermentation of corn starch or molasses. The ready availability of propylene in the 1960s led to routes based on the dehydrogenation of isopropyl alcohol or cumene peroxidation.
(1) By Cumene Oxidation (Hock Process).
Propene is added to benzene [71-43-2] to form cumene [98-82-8], which is then oxidized by air to cumene hydroperoxide, and cleaved in the presence of an acid catalyst like zeolite. Phenol [108-95-2] and acetone [67-64-1] produced in the process are recovered by distillation. Ratio of phenol to acetone is 1:0.6.
(2) By Dehydrogenation of 2-proponal
The hydration of propene [115-07-1] gives 2-propanol [67-63-0], which is then dehydrogenated to acetone. In the United States a C3 stream containing 40 – 60 % propene is used for the manufacture of 2-propanol. A large number of catalysts for 2-propanol dehydrogenation have been studied, including copper, zinc, and lead metals, as well as metal oxides, e.g., zinc oxide, copper oxide, chromium-activated copper oxide, manganese oxide, and magnesium oxide. Inert supports, such as pumice, may be used.
CH3CH=CH2 CH3CH(OH)CH3 CH3COCH3 +H2
(3) By catalytic oxidation of Propene (Wacker-Hoechst).
The process is analogous to the oxidation of ethylene to acetaldehyde by theWacker process. The catalyst solution typically contains 0.045M Palladium (II) chloride, 1.8M Copper (II) Chloride, and acetic acid. The reaction usually is carried out in two alternating stages. In the first stage, air is used to oxidize the metal ions to the +2 oxidation state. In the second, air is removed and propene added. Palladium (II) oxidizes propene, and the resulting Palladium (I) is reoxidized by the pool of copper (II). Besides propionaldehyde, chlorinated carbonyl compounds and carbon