Ilmenite Market Insights: Unveiling Key Drivers and Restraints |...

Ilmenite Market Insights: Unveiling Key Drivers and Restraints

Posted 2024-03-11 09:10:16

Ilmenite: A Primary Source of Titanium Dioxide

Formation and Deposits

Ilmenite, also known as manaccanite, is a titanium-iron oxide mineral with the formula FeTiO3. It is a weakly magnetic black or steel-gray solid. Ilmenite forms in igneous and metamorphic rocks as a primary mineral. It crystallizes in the trigonal-hexagonal system and most often occurs in a massive, granular or lamellar forms. Ilmenite forms as a volcanic and hypabyssal rock-forming mineral. Hydrothermal solutions also deposit ilmenite in veins and breccia zones. Major ilmenite deposits are found in Australia, South Africa, Canada, Ukraine and India. The largest deposits are located near Beach Lake in Ontario, Canada and near Prairie Lake in Australia.

Chemical Composition and Properties

Chemically, ilmenite is an iron(II) titanium oxide. It typically contains 50-52% TiO2 and 32-38% FeO. Ilmenite also contains small amounts of MgO, MnO and calcium contaminants. The mineral is black to steel-gray colored with a submetallic to dull luster. It has a hardness of 5-6.5 on the Mohs scale and a moderate specific gravity ranging from 4.7-5 g/cm3. Ilmenite is weakly magnetic due to its iron content. It tends to alter to leucoxene, pseudobrookite and rutile under weathering conditions near the Earth's surface. When heated in air, ilmenite oxidizes to a mixture of iron oxide and titanium dioxide.

Economic Significance and Uses

Ilmenite is the primary industrial source of titanium dioxide, which is also known as titanium white. Titanium dioxide has a variety of applications due to its brightness and very high refractive index. It is widely used as a pigment in paints, plastics, paper, inks, foods and other materials. Titanium dioxide imparts a brilliant white color and opacity to products while remaining non-toxic. As a pigment, it is valued for its hiding power and tinting strength. Globally, titanium dioxide demand exceeds 6 million metric tons per year. The paint and plastics industries combined account for approximately 90% of titanium dioxide usage.

Ilmenite is refined to produce commercial grade titanium dioxide through two main processes - sulfate and chloride methods. The sulfate method is more complex but yields higher grades of pigment. In this process, ilmenite is digested with sulfuric acid to separate impurities like iron. The resulting titanium sulfate solution is then hydrolyzed to form titanium dioxide pigment and residual iron sulfate. The chloride method uses chlorination to convert ilmenite to synthetic rutile, which is fed into a chloride slag process to extract pigment grade titanium dioxide. Around 95% of ilmenite mined globally is destined for titanium dioxide production.

Mining and Refining Processes

Mining ilmenite deposits involves open pit or underground methods based on the deposit type and economics. At the mining site, overburden rock is first removed to access the ilmenite orebody. The run of mine ore is dug out using heavy earthmoving equipment like hydraulic excavators and trucks. The ore is hauled to a processing facility where it undergoes size reduction using crushers and grinders. Magnetic separation is employed to concentrate the ilmenite content. This separates the weakly magnetic ilmenite from non-magnetic gangue minerals like silicates, quartz and iron sulfides.

The ilmenite concentrate is upgraded to synthetic rutile through various smelting and leaching operations depending on the feed mixture. This involves stages like chlorination roasting, acid leaching and catalytic hydrogen reduction. Synthetic rutile is a high purity TiO2 product suitable as feedstock for pigment production. The final titanium dioxide pigment is obtained through chloride slag or sulfate processes as described above. Additional finishing operations yield different grades of anatase or rutile pigment optimized for specific end use applications. Strict quality standards are followed during refining to meet customer requirements in the pigment industry.

Outlook and Sustainability Issues

Global ilmenite reserves are sufficient to meet demand for many decades at current production levels. Major producers like Rio Tinto, Vale, Chemours and others are engaged in exploration to discover new reserves and expand mining operations. Efforts are also on to produce titanium metal and alloys from ilmenite. Recycling of titanium scrap helps manage resources and reduce mining impacts. However, issues like land use, emissions, water usage and waste generation during mining and processing require ongoing attention. Industry-wide programs focus on environmental stewardship and sustainability performance. Minimizing energy consumption through efficient processes also benefits producers. On the whole, ilmenite will continue supplying the titanium needs of various industries into the foreseeable future.