| 摘要 |
<p>Process of producing titanium dioxide of pigment quality, by chemically processing previously enriched and purified anatase ore, herein denominated Upgraded Anatase Concentrate, through digestion with sulphuric acid, maintenance of the reaction always in the form of a fluid suspension, utilization of high acid concentrations, as well as high tempertures, under boiling conditions, so as to separate from the liquid medium, after the digestion is completed, a crystallized cake of titanium sulphates, containing also the crystallized sulphates of most of the impurities still present in the ore, which, by means of a subsequent and easy dissolution with water or recycled black liquor, produces, in an effective way, the so-called 'black liquor', which is treated for producing the titanium dioxide by the usual other steps of the Sulphate Process, the whole process requiring a minimum consumption of acid and ensuring a minimum emission of polluting effluents.</p> |
