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Cuprous Acetaldehyde Catalysts

The Reaction. Acrolein has been produced commercially since 1938. The first commercial processes were based on the vapor-phase condensation of acetaldehyde and formaldehyde (1). In the 1940s a series of catalyst developments based on cuprous oxide and cupric selenites led to a vapor-phase propylene oxidation route to acrolein (7,8). In 1959 Shell was the first to commercialize this propylene oxidation to acrolein process. These early propylene oxidation catalysts were capable of only low per pass propylene conversions (ca 15%) and therefore required significant recycle of unreacted propylene (9—11). [Pg.123]

Propylene oxide is also produced in Hquid-phase homogeneous oxidation reactions using various molybdenum-containing catalysts (209,210), cuprous oxide (211), rhenium compounds (212), or an organomonovalent gold(I) complex (213). Whereas gas-phase oxidation of propylene on silver catalysts results primarily in propylene oxide, water, and carbon dioxide as products, the Hquid-phase oxidation of propylene results in an array of oxidation products, such as propylene oxide, acrolein, propylene glycol, acetone, acetaldehyde, and others. [Pg.141]

In the past, acrolein was produced by the gas phase condensation of acetaldehyde with formaldehyde on sodium silicate, until it was supplanted by the catalytic oxidation of propylene. Early catalysts based on cuprous oxide were only sufficiently selective at low conversions of propylene. The real breakthrough came with the discovery made by Sohio of bismuth molybdate catalysts, developed into formulations specifically optimized for the manufacture of acrylonitrile, acrolein, and methacrolein. [Pg.52]

Copper chloride complexes can be used as catalysts in a number of organic reactions. Examples include the Wacker process, which is the oxidization of ethylene to acetaldehyde by oxygen and aqueous Cu and Pd precatalysts (or, alternatively using iron catalysts) plus the synthesis of acrylonitrile from acetylene and hydrogen cyanide using CuCl. Cuprous chloride has also been used as a desulfiuizmg and... [Pg.948]

Conditions for the direct oxidation of propylene to acrolein include use of a catalyst of cuprous oxide deposited on granular silicon carbide, catalyst temperature of 375 C, feed stream composition by volume of 20 per cent propylene, 20 per cent air, and 60 per cent steam, and contact time of 1 sec. Recovery and primary purification of the acrolein from the reaction product are effected by quench scrubbing the reactor effluent with water and wth liquid propylene. The composition of the carbonylic compounds in the product is, approximately, acrolein, 90 per cent by weight acetaldehyde, 6 per cent propionaldehyde, 2 per cent and acetone, 2 per cent. At reaction temperatures of about 300 C and conversions of about 50 per cent, a selectivity to acrolein of about 40 per cent is reported for 10 per cent propylene-in-air mixtures. ... [Pg.531]


See other pages where Cuprous Acetaldehyde Catalysts is mentioned: [Pg.680]    [Pg.680]    [Pg.680]    [Pg.680]    [Pg.680]    [Pg.680]    [Pg.680]    [Pg.680]    [Pg.51]    [Pg.74]    [Pg.149]    [Pg.298]    [Pg.5]    [Pg.51]    [Pg.567]    [Pg.229]    [Pg.51]    [Pg.161]    [Pg.146]    [Pg.80]   
See also in sourсe #XX -- [ Pg.74 ]

See also in sourсe #XX -- [ Pg.74 ]

See also in sourсe #XX -- [ Pg.74 ]

See also in sourсe #XX -- [ Pg.74 ]

See also in sourсe #XX -- [ Pg.74 ]




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