Malaysia: Advanced Materials from Malaysian Ilmenite Through Thermal Processing

Thermal processes have great potential to process ilmenite more sustainably, if compared to processing with the present popular chemical route. Nowadays, ilmenite is mainly processed for its titanium content that is for instance widely used as a white pigment in paint. Nanotitania possibly produced using the thermal processing route, has many potential applications due to its greater photocatalytic activity, as a result of its high surface area. Ilmenite or iron ore is mainly used as the source of TiO₂. It is a weakly magnetic iron black or steel grey mineral, found in metamorphic and plutonic rock. Ilmenite is primarily found in massive ore deposits or secondary alluvial deposits that contain heavy minerals. Ilmenite is usually treated with concentrated sulphuric acid and titanium oxygen sulphate is selectively extracted and converted into titanium dioxide. During the last stage of the process, the hydrated titanium dioxide is heated to produce crystals of anatase or rutile. This process is called sulphate process. Titanium dioxide, also known as titanium (IV) oxide or titania, is the naturally occurring oxide of titanium, with the chemical formula TiO₂. Titanium dioxide occurs in nature as rutile, anatase and brookite. Rutile is the next most abundant material and contains around 98% titanium dioxide in its ore. The metastable anatase and brookite phases convert irreversibly to the equilibrium rutile phase upon heating above temperatures in the range of 600–800°C. TiO₂ is usually a white powder that is widely used as an ingredient of white pigment, white plastic and white paper. These three products account for about 80% of the world's titanium dioxide consumption. It is also used for cosmetic products since it absorbs ultraviolet light. The rest is used in other applications such as the production of technical pure titanium, glass and glass ceramics, electrical ceramics, catalysts, electric conductors and chemicals.