Purification of silica sands

• US 2,891,844 A
• Filed: 04/02/1956
• Issued: 06/23/1959
• Est. Priority Date: 08/08/1955
• Status: Expired due to Term

• Current Assignee: William Adams Frederick
• Original Assignee: William Adams Frederick
• Inventors: WILLIAM ADAMS FREDERICK
• Application Number:
  US03/575,355
• Time in Patent Office: 1,177 Days
• US Class Current: 423/340
• CPC Class Codes: C03C 1/022 Purification of silica sand or other minerals
• CPC Class Codes: C04B 33/06 Rendering lime harmless
• CPC Class Codes: C04B 33/30 Drying methods

Claims

1. A PROCESS FOR THE PURIFICATION OF SILICA SANDS BY THE REDUCTION OF THE ASSOCIATED SURFACE IRON OXIDE CONTENT THEREOF TO A FRACTION NOT EXCEDDING ABOUT ONE HALF OF THE SAID ORIGINAL SURFACE IRON OXIDE CONTENT, WHICH PROCESS CONSISTS IN SUBJECTING THE SAID TO TREATMENT WITH A HOT AQUEOUS SOLUTION, AT A TEMPERATURE OF THE ORDER OF ABOUT 70*C. TO 90*C., CONTAINING A SMALL QUANTITY OF SULPHURIC ACID OF THE ORDER OF ABOUT 1 TO 2 PERCENT BY WEIGHT OF THE SAID SOLUTION AND A SMALLER QUANTITY, OF THE ORDER OF ABOUT 1 TO 10 PERCENT BY WEIGHT OF THE SULPHURIC ACID, OF A SOLUBLE INORGANIC CHLORIDE WHICH DISSOLVES IN THE SAID SOLUTION WITHOUT THE FORMATION OF AN INSOLUBLE SULPHATE, IN THE PRESENCE OF METALLIC COPPER HAVING A ARGE SURFACE AREA SO AS TO GIVE AN AMPLE METALLIC SURFACE CONTACT FOR THE SAND AND SOLUTION DURING THE PURIFICATION TREATMENT.