Method for purification of acetonitrile
AssigneeCryodyne Technologies, Inc.
InventorsBarry W. Himes, R. Clive Greenough
Life of this patent
Estimating the term…
Abstract
Acetonitrile is purified by treatment with ozone. After ozone treatment is ended, acetonitrile is passed through packed columns of molecular sieve, activated alumina and charcoal or graphitized carbon; the process results in virtually pure acetonitrile obtained at an efficiency unachievable by prior art processes.
Claims14
A combination method for removal of deleterious impurities from acetonitrile of a total starting impurity amount of above 10 ppm wherein the deleterious impurities are at least water, oxazole, acrylonitrile, crotonitrile, acetamide, methacrylonitrile, and methyloxazole, comprising:
- treating at ambient temperature acetonitrile with ozone for a time sufficient to oxidize the deleterious impurities in said acetonitrile;
- and, then passing the thus ozone treated acetonitrile through columns of at least a), a) and b), or a), b) and c) and wherein a) is a molecular sieve;
- b) is activated alumina, zirconia or silica gel and c) is charcoal or graphitized carbon, whereby a substantially impurity free acetonitrile is obtained wherein each of the deleterious impurities present are substantially entirely removed as determined spectrographically.
The method as defined in claim i-, wherein a major amount of aromatic impurities are removed by treatment with charcoal and then the acetonitrile treated with ozone and the acetonitrile then passed through columns a), a) and b), or a), b) and c).
Dependencies are inferred from the claim text.