Method for the preparation of ultra high purity sio2 in a porous bead form

Abstract

Abstract THERE IS DISCLOSED THE PREPARATION OF HIGH PURITY, SILICON OXIDE IN THE FORM OF POROUS BEADS OF A HIGH SURFACE AREA BY HYDROLYZING A SILICON ALKOXIDE DISSOLVED IN A HYDROXYL CONTAINING ORGANIC SOLVENT WITH LESS THAN A STOICHIOMETRIC AMOUNT OF WATER SO AS TO PROVIDE A PARTIALLY HYDROLYZED SOLUBLE INTERMEDIATE PRODUCT. THE RESULTING PARTIALLY HYDROLYZED INTERMEDIATE PRODUCT IS THEN TREATED WITH AN IMMISCIBLE ORGANIC MEDIUM SO AS TO FORM A DISCONTINUOUS PHASE OF LIQUID PARTIALLY HYDROLYZED INTERMEDIATE PRODUCT DISPERSED INA CONTINUOUS PHASE OF ORGANIC MEDIUM. THE DISPERSED INTERMEDIATE PRODUCT IS THEN TREATED WITH A BASE AND A QUANTITY OF WATER SUFFICIENT TO HYDROLYZE RESIDUAL ALKOXY GROUPS IN THE DISPERSED INTERMEDIATE PRODUCT. THE RESULTING MIXTURE IS STIRRED UNTIL THE DISPERSED INTERMEDIATE IS CONVERTED TO FIRM, HARD, SOLID, POROUS BEADS OF SILICON OXIDE. THE BEADS ARE TYPICALLY RECOVERED BY FILTRATION AND EVAPORATION OF NON-SOLID RESIDUES OR BY LIKE METHOD.

Inventors

• 👤 Ian M Thomas

Bibliographic Details