Effects of mineralogical and textural characteristics of ilmenite concentrate on synthetic rutile production

摘要

The effect of mineralogy and texture of Qara-aghaj ilmenite concentrate on titanium dioxide prepared via reduction-slagging acid leaching process as a raw material in chloride route was investigated. The concentrate contains 44.5 % TiO2 and its content in ilmenite lattice varies from 41.6-48 %. Hematite exsolved lamellae inside ilmenite which affect the reduction process positively are host of the most of the Cr and V as pigment colorizer metals. Apatite fine inclusions inside ilmenite as the source of Ca and P could have negative effects on synthetic rutile. Spinel ultrafine particles inside ilmenite containing Al and Si could also affect the synthetic rutile negatively. The other important elements which have been substituted in ilmenite lattice are Mg and Mn. The prepared titanium dioxide concentrate containing 91 % TiO_2 and 0.6 % Fe_2O_3 is mainly formed by rutile and small amount of anatase and Ti_2O_3 phases. The solid solution of rutile inside Ti_2O_3 was also observed. The content of Cr, V, Mn, and Al are decreased to permissible amount during slagging and leaching process while the quantity of other impurities such as Mg, Si, and Ca are relatively high in the product, and they cause some difficulties in pigment production via chloride route. The Mg and Ca sourced from ilmenite lattice and apatite inclusions, respectively, can affect the precipitation process. So, it is predicted that Qara-aghaj ilmenite concentrate will be suitable for sulfate route, but it is necessary to investigate comprehensively.