Abstract: An improved process for producing titanium dioxide by reacting a titanium dioxide ore with chlorine to produce a gaseous stream containing titanium tetrachloride, condensing titanium tetrachloride from the gaseous stream containing titanium tetrachloride to produce chlorinator tail gas, vaporizing the condensed titanium tetrachloride, reacting the vaporized titanium tetrachloride with oxygen to produce a gaseous stream containing titanium dioxide particles and chlorine, separating the titanium dioxide particles from the gaseous stream containing titanium dioxide particles and chlorine to produce burner tail gas, analyzing the chlorinator tail gas for residual chlorine to control the step of reacting the titanium dioxide ore with chlorine, analyzing the burner tail gas for oxygen to control the step of reacting the condensed titanium tetrachloride with oxygen. The improvement is to analyze the chlorinator tail gas for residual chlorine (and/or the burner tail gas for oxygen) using an on-line analyzer.

Abstract: A method to determine the concentration ratio of carbon monoxide to carbon dioxide in the gaseous product of a fluidized bed reactor for producing titanium tetrachloride. The hot fluidized bed of the reactor is used as the source of infrared radiation which radiation is directed through the gaseous products in upper portion of the reactor through a window in the reactor to an infrared spectrometer. The concentration ratio can be used to control the temperature of the fluidized bed reactor by controlling the amount of cool titanium tetrachloride that is introduced into the reactor.

Abstract: A method to determine the concentration ratio of carbon monoxide to carbon dioxide in the gaseous product of a fluidized bed reactor for producing titanium tetrachloride. The hot fluidized bed of the reactor is used as the source of infrared radiation which radiation is directed through the gaseous products in upper portion of the reactor through a window in the reactor to an infrared spectrometer. The concentration ratio can be used to control the temperature of the fluidized bed reactor by controlling the amount of cool titanium tetrachloride that is introduced into the reactor.

Abstract: An improved process for producing titanium dioxide by reacting a titanium dioxide ore with chlorine to produce a gaseous stream containing titanium tetrachloride, condensing titanium tetrachloride from the gaseous stream containing titanium tetrachloride to produce chlorinator tail gas, vaporizing the condensed titanium tetrachloride, reacting the vaporized titanium tetrachloride with oxygen to produce a gaseous stream containing titanium dioxide particles and chlorine, separating the titanium dioxide particles from the gaseous stream containing titanium dioxide particles and chlorine to produce burner tail gas, analyzing the chlorinator tail gas for residual chlorine to control the step of reacting the titanium dioxide ore with chlorine, analyzing the burner tail gas for oxygen to control the step of reacting the condensed titanium tetrachloride with oxygen. The improvement is to analyze the chlorinator tail gas for residual chlorine (and/or the burner tail gas for oxygen) using an on-line analyzer.