Recovery of titanium tetrachloride

A process for the recovery of titanium tetrachloride by separating it from iron chloride contained in an effluent;

• the effluent comprising a gaseous mixture of titanium tetrachloride and iron chloride which is predominantly in the form of ferric chloride, and resulting from a process comprising the steps of continously feeding into a fluidised bed reactor solids comprising 60% to 80% by weight of ilmenite ore and from 20% to 40% by weight of coke;
• maintaining the solids in the fluidised state by means of a fluidising gas comprising from 75% to 100% by volume of chlorine, from 0% to 15% by volume of an inert gas and from 0% to 10% by volume of oxygen, maintaining the temperature of the fluidised solids in the range from 850.degree. C. to 1000.degree. C. and controlling the rate of feed of solids to maintain the level of the surface of the fluidised solids at a point in the lower half of the reactor, the separation of the titanium tetrachloride being effected by passing the effluent from the surface of the fluidised bed upwardly through the upper half of the reactor, while cooling it to a temperature in the range from 500.degree. C. to 800.degree. C. by incorporating liquid titanium tetrachloride therein, mixing the cooled effluent at or near the top of the reactor, with oxygen in a quantity 5% to 100% in excess of the quantity required in theory to oxidise the ferric chloride content of the effluent to produce particles of ferric oxide, the velocity of the resulting mixture of the remaining gases of the effluent, oxygen and chlorine being sufficient to entrain the said particles, removing the said mixture and entrained particles from the reactor, adjusting the temperature of the removed mixture firstly to above 250.degree. C. but low enough to solidify any calcium or magnesium chlorides which may be present therein and removing ferric oxide particles and any resulting solid calcium or magnesium chlorides;
• further cooling the mixture to a temperature in the range from 250.degree. C. to 130.degree. C. to solidify any residual ferric chloride, removing any resulting particles of ferric chloride from the mixture;
• further cooling the mixture to below 130.degree. C. to condense titanium tetrachloride therefrom, recovering the condensed titanium tetrachloride;
• recovering residual chlorine from the remaining vapours by selective absorption in titanium tetrachloride followed by desorption, and recycling the recovered chlorine into the fluiding gas, incorporating residual ferric chloride in the solids in the fluidised bed reactor and utilising a proportion of the liquid titanium tetrachloride recovered to cool the effluent from the fluidised bed.