Removal of colouring materials from Egyptian albite ore

Abstract

Albite (sodium feldspar) is widely used in glass and ceramic industries. The presence of colouring materials such as titanium dioxide and iron oxide reduces the quality of feldspar. To use albite feldspar in fine ceramic and high quality glass, colouring materials should be removed. This work aims to remove the colouring materials in the albite by using both dry magnetic separation and flotation techniques. The experimental programme involves crushing, grinding, sieving, dry magnetic separation and indirect flotation of colouring materials. The grinding was used to prepare different sizes varied from 100 to 500 µm for dry magnetic separation and flotation. The different parameters such as the effect of particle size, the dosage of sodium oleate and the effect of pH were studied. Results of flotation of colouring material and high intensity magnetic separation showed that at sizes varied from 500 to 300 µm, ∼90% of iron oxide and titanium oxide were removed. The iron oxide decreased from 1˙85 to 0˙2% where the titanium oxide decreased from 0˙35 to 0˙03% in the concentrate. This concentrate could be suitable for fine ceramic and high quality glass. In the case of flotation of fine fraction from 200 to 100 µm, the removal percentages of iron and titanium were ∼86 and 72˙6% respectively.