Production of Rutile and Iron from Ilmenite.
U S Pat 3 767 378 1973 Oct; :
Ilmenite is reduced by treating with h2 for 2 h at 860 deg. C. Treating with coke for 4 h at 1,100 deg. C is also effective. The reduced ilmenite is then treated with CO in the presence of ammonium polysulfide solution for 204 h at 110 deg.-150 Deg. C and 60-100 atm to form fe(co)5 which is then removed by volatilization, leaving rutile. The fe(co)5 is decomposed to produce metallic iron.
U.S. Pat. 3,767,378; Oct. 23, 1973; Chem. Abstr. 80:111,152X