Production of silicon dioxide

Claim 1

PROCESS FOR THE MANUFACTURE OF SILICON DIOXIDE OF USE IN THE RUBBER INDUSTRY AS A FILLER BY OXIDATION IN THE ABSENCE OF ANY SUBSTANTIAL HYDROLYSIS, OF VAPOURISED SILICON TETRACHLORIDE WITH GAS COMPRISING FREE OXYGEN, AS SUBSTANTIALLY ENTIRELY THE ONLY REACTANTS, COMPRISING FEEDING THE REACTANTS INTO AS BED CONSISTING OF A HOT MASS OF PARTICULATE SOLID INERT MATERIAL HAVING A MEAN PARTICLE SIZE FROM ABOUT 40U TO ABOUT 1,000U THE VELOCITY OF FEED OF AT LEAST ONE OF SAID REACTANTS BEING SUFFICIENT TO MAINTAIN SAID BED IN A FLUIDISED STATE, SO THAT AT A TEMPERATURE IN THE RANGE FROM ABOUT 500*C. TO ABOUT 1,300C. SAID SILICON TETRACHLORIDE AND SAID FREE OXYGEN REACT WITHIN SAID BED TO FORM SILICON DIOXIDE AND CHLORINE WHICH ARE CONTINUOUSLY DELIVERED FROM THE BED, THE SILICON DIOXIDE CONSISTING OF AGGREGATES OF FINE PARTICLES BEING IN A FINE FLOCCULENT STATE ENTRAINED IN THE CHLORINE, SUBSTANTIALLY ALL OF THE SILICON DIOXIDE SO PRODUCED BEING ENTRAINED IN THE PRODUCT GASES, AND THEREAFTER SEPARATING THE SILICON DIOXIDE FROM THE CHLORINE.