Patent ID: 6290924
Filing Date: 2001-09-18
Classification: C01B,C01P,C08K,C09C

Abstract:
A process for the production of silica beads having a substantially spherical morphology and a mean particle size of at least 80 .mu.m, a maximum BET specific surface area of 130 m.sup.2 /g, a fill density in paced state (DRT) of greater than 0.32, and a total pore volume of at least 1.6 cm.sup.3 /g, including providing a silica suspension by reacting a silicate with an acidifying agent and precipitating silica therefrom, and then drying/atomizing such precipitate, said silica precipitation and atomization comprising:(i) preparing a base mixture containing at least a portion of the silicate required for complete reaction and an electrolyte;(ii) adding said acidifying agent to such base mixture as to adjust the pH thereof to a value of about 7;(iii) optionally, simultaneously adding any remaining silicate and any required additional acidifying agent to said base mixture;(iv) adjusting the dry solids content of the resulting suspension to at least 18% and adjusting the pH thereof to a value of at least 4; and(v) atomizing such adjusted suspension to dryness.