Producing chlorination-grade feedstock from domestic ilmenite - laboratory and pilot plant studies.
Elger-GW; Wright-JB; Tress-JE; Bell-HE; Jordan-RR
Albany, OR: U.S. Department of the Interior, Bureau of Mines, RI 9002, 1986 Jan; :1-24
The Bureau of Mines investigated the conversion, at both laboratory and pilot plant scale, of a low-grade ilmenite to chlorination-grade feedstock that could substitute for imported rutile used to produce titanium tetrachloride. The concentrate was derived from the Tahawus, New York, lode deposit of ilmenite-magnetite in rock that contains anorthosite and gabbro. Charges of the ilmenite concentrate, containing 46.6 wt pct TiO2 blended with soda ash, were carbothermically reduced in an electric arc furnace, which separated most of the iron and left a high-titanium slag. However, the slag contained Ca, Mg, and Mn constituents that rendered the material unsuitable for continuous chlorination by causing plugging problems. After being ground and pelletized, the slag was reacted with SO2 and air at 700 deg to 900 deg C, which selectively converted the harmful impurities to soluble compounds that were removed in a subsequent water or dilute HCl leach. In laboratory tests, the combined levels of harmful impurities were decreased from 5 to as low as 0.5 wt pct in leached slags. In pilot plant tests, leached slags sulfated at a rate of 10 lb/h averaged 85.5 wt pct TiO2 with pertinent impurity levels averaging 1.86 Wt pct. The leached slag was successfully chlorinated in a laboratory fluidized-bed reactor at 950 deg C to extract titanium as TiCl4.
Slags; Upgrading; Ilmenite; Extractive-metallurgy; Titanium-oxides
IH; Report of Investigations
NTIS Accession No.
Albany, OR: U.S. Department of the Interior, Bureau of Mines, RI 9002