Patents

An improved process for the production of high grade synthetic rutile

Pawathau Narayanan Nair Mohan Das, Ephraim Jeya Kumari, Sreedhran Sasibhushanan, Melay Eriyat Kochu Janaki

An improved process for the production of high grade synthetic rutile which comprises: a) heating ilmenite with coal at a temperature in the range of 850-1250°C with 30 – 100% coal for 0.5 to 8 hrs till the complete reduction of iron oxide to metallic state. b) cooling rapidly the resultant of step (a) to room temperature and removing the unreacted coal and ash by known physical methods selected from sieving, magnetic separation, c) oxidising the product obtained in step (b) in presence of air and catalyst in an aqueous medium comprising of 0.5 – 2.5% NH4CI and 0.1 to 10% of carbonyl compounds at a solid liquid ratio of 0.2 to 0.6% at a temperature of 20 to 35°C for a period of 1 – 8 hrs, d) separating the iron oxide from the said product obtained in step (c) by washing with water, e) rutilating the product obtained in step (d) after removal of iron oxide by heating in presence of air at a temperature in the range of 650 – 900°C. for 0.15 to 2 hrs., f) leaching the said rutilated product obtained in step (e) with dilute mineral acid such as herein described, in the conventional way at a temperature of 50 – 100°C and recovering the synthetic rutile by filtration, washing and drying.