Chemistry of inorganic compounds – Halogen or compound thereof – Hydrogen halide
Patent
1996-09-11
1999-03-02
Cintins, Ivars
Chemistry of inorganic compounds
Halogen or compound thereof
Hydrogen halide
203 41, 210662, 210664, 210683, 423483, C01B 719
Patent
active
058766855
ABSTRACT:
A method for the removal and purification of substantially all of the fluoride ions contained in a solution containing greater than 10 parts per million (ppm) fluoride ion, a mixture of other anions, silicon in the form of a fluorosilicic acid, silicic acid, silicates, or silicon tetrafluoride, and optionally also containing complex metal fluorides, to produce an ultrapure hydrofluoric acid, comprising the steps of (a) adjusting the pH of the solution to an alkaline pH to hydrolyze the fluorosilicic acid and any complex metal fluorides; (b) removing the fluoride ions and other anions from the solution by passing the solution through an ion exchange resin, where the ion exchange resin is adapted to adsorb substantially all of the fluoride passed over the ion exchange resin; (c) displacing the fluoride ions and other anions bound to the ion exchange resin, thereby forming a mixture of anions in an effluent emanating from resin; (d) optionally concentrating the effluent at a high pH and then lowering the pH; and (e) distilling the mixture of anions in the effluent from a sulfuric acid solution to generate ultrapure hydrofluoric acid. An apparatus useful for practicing the method is also disclosed.
REFERENCES:
patent: 4062930 (1977-12-01), Zawadzki et al.
patent: 4067957 (1978-01-01), Worthington et al.
patent: 4144315 (1979-03-01), Worthington et al.
patent: 4655929 (1987-04-01), Tanaka et al.
patent: 4764276 (1988-08-01), Berry et al.
patent: 4898317 (1990-02-01), Ito et al.
patent: 4952386 (1990-08-01), Davison et al.
patent: 4965061 (1990-10-01), Berry et al.
patent: 5294305 (1994-03-01), Craft, Sr. et al.
Adams John A.
Blatt Christopher S.
Dornisch Dieter
Krulik Gerald A.
Persichini David W.
Cintins Ivars
IPEC Clean, Inc.
LandOfFree
Separation and purification of fluoride from industrial wastes does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Separation and purification of fluoride from industrial wastes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Separation and purification of fluoride from industrial wastes will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-419487