Back to results
US 6,187,973 B1Granted
Glycol purification
AssigneeScientific Design Company, Inc.
InventorMansoor Husain
Life of this patent
Estimating the term…
Abstract
Aqueous ethylene glycol solution containing aldehydes such as formaldehyde, acetaldehyde and the like is contacted with a solid bisulfite treated strong base anion exchange resin and a solution reduced in aldehydes content is separated.
Claims2
The method for reducing the aldehydes content of an aqueous aldehydes-containing ethylene glycol solution comprised of about 0.2 to 20 wt % ethylene glycol;
- about 80 to 99.7 wt % water and about 100 ppm to 1.0 wt % aldehydes which comprises contacting the solution with a solid bisulfite treated strong base anion exchange resin having quaternary ammonium functional groups in hydroxide form before bisulfite treatment.
Dependencies are inferred from the claim text.