Nl Industries

Donald G Cole

Joseph A Rahm

Achim Hartmann

Achim M Kulling

Hermann B Trub

A process is provided for the manufacture of titanium compounds and particularly titanium dioxide wherein excess titaniferous bearing material is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight at a temperature below about 140.degree. C., and in the presence of a reducing agent which affects the reduction of ferric iron to ferrous iron. Thereafter, the titanium sulfate may be recovered or further processed to provide titanium dioxide hydrate accompanied by recycling the spent acid for reaction with the titaniferous bearing material charged to the process. The titanium hydrate may be calcined to provide titanium dioxide.

Process for manufacturing titanium compounds using a reducing agent

A process is provided for the manufacture of titanium dioxide pigment wherein excess ilmenite ore is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight in the presence of an iron reductant, and in preferably at least two stages wherein the first stage is maintained at a temperature up to about 140.degree. C. and the second stage is conducted at a lower temperature (than the first stage) which is below about 100.degree. C. to provide a salt solution of titanium and iron. Thereafter, the titanium is hydrolyzed to provide titanium dioxide hydrate accompanied by recycling the spent acid from the hydrolysis for reaction with the ilmenite ore charged to the process. The titanium hydrate is calcined to provide titanium dioxide pigment.

Process for manufacturing titanium dioxide

A process is provided wherein solid mixtures of metal chlorides of, for example, ferric chloride, ferrous chloride, vanadium chloride and chromium chloride are (1) mixed with an alkaline material such as, for example, calcium oxide, calcium hydroxide and calcium carbonate, followed (2) by adding water to the resulting mixture to granulate said mixture whereby the metal chlorides are rendered substantially insoluble in water.

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Pulheim, Germany

Donald G Cole