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.
Claims24
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, 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.
A method for clarifying 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, wherein said microparticles are characterized as being anionic or amphoteric and have a weight average molecular weight of greater than 60 Million Da;
- and
- separating the phosphoric acid from the insoluble precipitates, thereby clarifying the phosphoric acid.
In a wet process phosphoric acid production process comprising the steps of digesting
- phosphate rock in a slurry containing sulfuric acid, thereby releasing phosphoric acid and forming suspended insoluble precipitates, and then separating the phosphoric acid from said suspended insoluble precipitates by a filtration and/or clarifying aid, the improvement comprising:
- adding to said slurry an effective amount of a reagent comprising polymeric microparticles, wherein said microparticles are characterized as being anionic or amphoteric and have a weight average molecular weight of greater than 60 Million Da, thereby enhancing the filtration rate and/or clarity of the phosphoric acid.
Dependencies are inferred from the claim text.