Process for preparing pigmentary metal oxide

Claim 2

A process according to claim 1 wherein the radiant heat source is maintained at temperatures from 3,000* F. to 20,000* F.

Claim 3

A process according to claim 1 wherein metal halide and oxygen are introduced into said reaction zone at below reaction temperature.

Claim 4

A process according to claim 4 wherein metal halide and less than a stoichiometric amount of oxygen, based on metal halide, is introduced into said reaction zone below reaction temperature and wherein oxygen is heated by passage through said zone of radiant heat.

Claim 5

A process according to claim 1 wherein the gas which is heated by passage through said zone of radiant heat is oxygen, and said oxygen is heated by passage in direct heat exchange relationship with said radiant heat source and wherein vaporous metal halide is introduced into said heated oxygen after it has passed said zone of radiant heat.

Claim 6

A process according to claim 6 wherein said vaporous metal halide is fed into said heated oxygen from a stream disposed around said heated oxygen and enters the perimeter of the heated oxygen.

Claim 7

A process according to claim 6 wherein said vaporous metal halide is Titanium tetrachloride and the temperature of said vaporous titanium tetrachloride is below 700* C.

Claim 8

A process according to claim 1 wherein said radiant heat source is a carbon monoxide flame.

Claim 9

In a process for producing pigmentary titanium dioxide by vapor phase reaction of the reactants oxygen and titanium tetrachloride wherein said reactants are mixed in a reaction zone in a reactor and titanium dioxide is produced thereby and removed from said reactor and wherein vaporous titanium tetrachloride is introduced into said reaction zone at below reaction temperature, the improvement which comprises promoting mixing of reactants oxygen and titanium tetrachloride in said reaction zone at reaction temperatures and supplying sufficient heat to said reaction zone to maintain said reaction by heating oxygen-containing gas to above reaction temperatures by passage through a zone having a radiant heat source maintained at at least 3, 000* F. and openly connected with said reaction zone, said radiant heat source being spaced from said reaction zone and visually in line therewith, forwarding thus heated oxygen-containing gas directly into aid reaction zone along said visual line, and mixing said vaporous titanium tetrachloride with said heated oxygen-containing gas at reaction temperatures in said reaction zone.

Claim 10

The process according to claim 10 wherein said radiant heat source is maintained at temperatures of from 3,000* F. to 20, 000* F.

Claim 11

In a process for producing pigmentary titanium dioxide by vapor phase reaction of reactants titanium tetrachloride and oxygen at temperatures above 800* C. wherein said reactants are mixed in a reaction zone in a reactor and titanium dioxide is produced thereby and removed from said reactor and wherein vaporous titanium tetrachloride is introduced into said reaction zone at temperatures below 700* C., the improvement which comprises promoting mixing of reactants titanium tetrachloride and oxygen in said reaction zone at reaction temperatures and supplying sufficient heat to said reaction zone to maintain said reaction by heating oxygen-containing gas to above reaction temperatures by passage through a zone having a radiant heat source maintained at temperatures of from 3,000* F. to 20,000* F. and openly connected with said reaction zone by a direct passageway, said radiant heat source being spaced from said reaction zone and visually in line therewith, forwarding thus heated oxygen-containing gas through said passageway to said reaction zone along said visual line, and mixing said vaporous titanium tetrachloride with said heated oxygen-containing gas at reaction temperatures in said reaction zone.