Process for producing fluosilicates

Abstract

Abstract A PROCESS FOR THE MANUFACTURE OF COMMERCIALLY PURE SODIUM FLUOSILICATE FROM WET PROCESS PHOSPHORIC ACID (WPA) BY REACTING A SODIUM SALT PREFERABLY SODIUM CHLORIDE WITH THE FLUOSILICIC ACID PRESENT IN THE PHOSPHORIC ACID UNDER CONDITIONS OF MODERATE AGITATION CHARACTERIZED BY A REYNOLDS NUMBER OF BETWEEN 7600 AND 8300, THEREBY PRECIPITATING THE SODIUM FLUOSILICATES AS A PARTICLE HAVING A SIZE BETWEEN 200 MESH AND 325 MESH. THE REACTANT CONTAINING THE PRECIPITATE IS DISCHARGED AS A SLURRY TO A SETTLING TANK WHERE THE PRECIPITATE IS SETTLED OUT AND THE CLARIFIED DEFLUORINATED ACID PASSED OUT IN A SEPARATE STREAM FOR FURTHER PROCESSING. THE SETTLED MUD IS THEN PASSED TO A CLASSIFIER WHERE GYPSUM AND OTHER SOLIDS ARE FLOATED OUT IN THE WASH, THE WASH AS OVERFLOW BEING RECYCLED TO THE MIXING REACTOR. THE CLASSIFIED SODIUM FLUOSILICATE IS FILTERED AND DRIED TO OBTAIN A COMMERCIALLY PURE SODIUMFLUOSILICATE. WET PROCESS PHOSPHORIC ACID CAN ALSO BE DEFLUORINATED BY REACTION WITH EITHER POTASSIUM OR BARIUM SALTS UNDER LIKE CONDITIONS. IN THE INSTANCE, EITHER POTASSIUM OR BARIUM FLUOSILICATE MAY BE RECOVERED. BY REACTING THE WET ACID WITH A MIXTURE OF SODIUM, POTASSIUM AND/OR BARIUM SALTS, A MIXED FLUOSILICATE PRODUCT CAN ALSO BE OBTAINED.

Inventors

• 👤 James E Barker
• 👤 Julian H Robinson

Bibliographic Details