ABSTRACT
The discovery by Shell that propylene could be oxidized to acrolein in the presence of a cuprous oxide catalyst led the move towards commercial processes. An aqueous solution of acrolein is obtained by passing the exit gases through cold water. The resultant acrolein, 95–96% pure, is stabilized with hydroquinone to minimizse polymerization. Acrolein yields of up to 85% are claimed based on propylene with 5–10% of acrylic acid. Copolymers of acrolein and acrylic acid are useful sequestering agents. Acrolein polymers can be used in textile treatment, paper reinforcement and photography. Liquid acrolein vaporizes easily; its vapours are twice as heavy as air and highly toxic. Acrolein will react explosively in the presence of alkalis, concentrated mineral acids, amines, sulphur dioxide, metal salts and oxidants. Acrolein is a dangerous fire hazard, because of the risk of flashback and explosion caused by polymerization.
