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US 5,629,443 AGranted
Highly purified acetonitrile and process for purifying crude acetonitrile
AssigneeAsahi Kasei Kogyo Kabushiki Kaisha
InventorsShigeo Nakamura, Shigeru Kurihara, Minoru Saitoh, Hideo Midorikawa
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Abstract
A process for purifying crude acetonitrile comprising: (1) a step of contacting crude acetonitrile with nascent oxygen, (2) a step of contacting the acetonitrile from step (1) with a solid base, and (3) a step of removing low-boiling compounds and high-boiling compounds from the acetonitrile from step (2), wherein the step (3) may be effected after the step (1) and before the step (2).
Claims29
A process for purifying crude acetonitrile having a UV absorbance at 200 nm of from 0.1 to 5 comprising:
- (1) a step of contacting crude acetonitrile with an ozone-containing gas in an amount from 1 to 10,000 times the volume of the crude acetonitrile,
- (2) a step of contacting the acetonitrile from step (1) with an anion exchange resin, wherein the contact temperature of the acetonitrile and the anion exchange resin is from -40.degree. to 80.degree. C.,
- (3) a step of removing low-boiling compounds and high-boiling compounds from the acetonitrile.
Dependencies are inferred from the claim text.