Source: {"pile_set_name": "USPTO Backgrounds"}

Acrolein is a material known to have toxic effects. Contact with acrolein is preferably avoided or minimized. It would be desirable if a method could be discovered which would remove acrolein from mixtures of other valuable materials in a selective fashion while removing essentially none of the other compound or compounds. For example, it is known to separate acrolein from acrylonitrile using extractive distillation with water. However, this technique will not work to extract acrolein from an aqueous solution of acrylonitrile when it is desirable to keep the acrylonitrile in the aqueous solution. The presence of acrolein in acrylonitrile solutions also results in the presence of an acrolein/cyanohydrin adduct, which is also to be avoided.
Some methods of removing, acrolein from waste gas include, but are not necessarily limited to, the use of membrane separation, catalytic oxidation, activated carbon, and silica gel containing an iron phthalocyanine catalyst. Catalytic oxidation and distillation at certain pH levels have also been used to remove acrolein from acrylonitrile. Other processes for removing acrolein from acrylonitrile include ion exchange resins and condensation, the latter procedure which has also been used to remove acrolein from acrylic acid. However, there remains a need for acrolein scavengers that can selectively react with acrolein relative to the other species in the solution.