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US 10,246,332 B2Granted
Polymeric microparticles as filtration and/or clarifying aids in phosphoric acid production
AssigneeCytec Industries Inc.
InventorLei Zhang
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Abstract
Processes for enhancing filtration rate and/or clarification of phosphoric acid produced by the wet process and containing suspended insoluble particulates by adding to one or more stage of the wet process phosphoric acid production stream an effective amount of a reagent including polymeric microparticles characterized as being anionic or amphoteric and having a weight average molecular weight of greater than 60 Million daltons are provided herein.
Claims19
A method for enhancing the filtration rate of phosphoric acid produced by the wet process and containing suspended insoluble precipitates, the method comprising:
- adding to the phosphoric acid at any stage of the phosphoric acid production process an effective amount of a reagent comprising polymeric microparticles crosslinked by a polyfunctional crosslinking agent selected from the group consisting of N,N′-methylenebisacrylamide;
- N,N′-methylenebismethacrylamide;
- polyethyleneglycol diacrylate;
- polyethyleneglycol dimethacrylate;
- N-vinyl acrylamide;
- triallylammonium salts;
- N-methylallylacrylamide;
- methylolacrylamide;
- glycidyl acrylate;
- divinylbenzene;
- acrolein;
- gyloxal;
- diepoxy compounds;
- epichlorohydrin;
- and mixtures thereof, wherein the polyfunctional crosslinking agent has a molar ratio from 90 molar parts per million to 5,000 molar parts per million based on the total mole % of monomers present in the polymeric microparticle, and wherein said microparticles are characterized as being anionic or amphoteric and have a weight average molecular weight of greater than 60 Million Da;
- and
- filtering the phosphoric acid, thereby enhancing the filtration rate of the phosphoric acid.
14 more elements
Dependencies are inferred from the claim text.