Method for the preparation of titanium hydrate

Claim 1

THE METHOD OF PREPARING A TITANIUM HYDRATE SUITABLE FOR THE MANUFACTURE OF TITANIUM PIGMENTS WHICH HAVE GOOD COLOR AND HIGH COVERING POWER, WHICH COMPRISES FIRST ADDING GRADUALLY TO HEATED WATER MAINTAINED AT A TEMPERATURE BETWEEN ABOUT 85*C. AND ABOUT 100*C. A SMALL AMOUNT OF A SEEDING AGENT COMPRISING A CONCENTRATED SOLUTION OF ILMENITE IN SULFURIC ACID FROM WHICH IRON HAS BEEN REMOVED TO A LEVEL CORRESPONDING TO A WEIGHT RATIO OF FESO4:TIO2 OF LESS THAN ABOUT 0.8:1 AND WHICH HAS BEEN CONCENTRATED TO A TIO2 CONTENT OF AT LEAST 200 GRAMS PER LITER, THEN HYDROLYZING AN UNCRYSTALLIZED AND UNCONCENTRATED SOLUTION OF ILMENITE HAVING A TITANIUM DIOXIDE CONTENT FROM ABOUT 110 TO ABOUT 150 GRAMS PERLITER IN SULFURIC ACID, SAID UNCONCENTRATED ILMENITE SOLUTION CONTAINING ABOVE ABOUT 80 GRAMS PER LITER OF FERROUS ION, BY ADDING SUCH SOLUTION GRADUALLY TO SAID MIXTURE OF SEEDING AGENT AND HEATED WATER MAINTAINED AT A TEMPERATURE BETWEEN ABOUT 85* AND ABOUT 100*C. UNTIL THE ADDITION IS COMPLETE, THE AMOUNT OF SEEDING AGENT COMPRISING AT LEAST 4% OF THE TOTAL VOLUME OF ILMENITE SOLUTION TO BE HYDROLYZED, THE PROPORTION OF ADDED ILMENITE SOLUTION COMPRISING BETWEEN ABOUT 75% AND ABOUT 96% OF THE TOTAL VOLUME OF SOLUTION AND SEEDED WATER, BOILING THE MIXTURE TO COMPLETE THE HYDROLYSIS, AND RECOVERING THE RESULTING TITANIUM HYDRATE.

Claim 2

THE METHOD OF PREPARING A TITANIUM HYDRATE SUITABLE FOR THE MANUFACTURE OF TITANIUM PIGMENTS WHICH HAVE GOOD COLOR AND HIGH COVERING POWER, WHICH COMPRISES FIRST ADDING GRADUALLY TO HEATED WATER MAINTAINED AT A TEMPERATURE BETWEEN ABOUT 85*C. AND ABOUT 100*C. A SMALL AMOUNT OF A SEEDING AGENT COMPRISING A CONCENTRATED SOLUTION OF ILMENITE IN SULFURIC ACID FROM WHICH IRON HAS BEEN REMOVED TO A LEVEL CORRESPONDING TO A WEIGHT RATIO OF FESO4:TIO2 OF LESS THAN ABOUT 0.8:1 AND WHICH HAS BEEN CONCENTRATED TO A TIO2 CONTENT OF AT LEAST 200 GRAMS PER LITER, THEN HYDROLYZING AN UNCRYSTALLIZED AND UNCONCENTRATED SOLUTION OF ILMENITE HAVING A TITANIUM DIOXIDE CONTENT FROM ABOUT 110 TO ABOUT 150 GRAMS PERLITER IN SULFURIC ACID, SAID UNCONCENTRATED ILMENITE SOLUTION CONTAINING ABOVE ABOUT 80 GRAMS PER LITER OF FERROUS ION, BY ADDING SUCH SOLUTION GRADUALLY TO SAID MIXTURE OF SEEDING AGENT AND HEATED WATER MAINTAINED AT A TEMPERATURE BETWEEN ABOUT 85* AND ABOUT 100*C. UNTIL THE ADDITION IS COMPLETE, THE AMOUNT OF SEEDING AGENT COMPRISING AT LEAST 4% OF THE TOTAL VOLUME OF ILMENITE SOLUTION TO BE HYDROLYZED, THE PROPORTION OF ADDED ILMENITE SOLUTION COMPRISING BETWEEN ABOUT 75% AND ABOUT 96% OF THE TOTAL VOLUME OF SOLUTION AND SEEDED WATER, BOILING THE MIXTURE TO COMPLETE THE HYDROLYSIS, AND RECOVERING THE RESULTING TITANIUM HYDRATE.