Leaching of ilmenite to produce titanium based materials: a review

Abstract

Naturally available ilmenite mineral is being used as a starting material to produce titanium based products that have wide applications. Transformation of ilmenite to different titanium based materials by strong and weak acid, and base digestion, is discussed. Effects of temperature, concentration of acid/base, reaction time on dissolution of ilmenite are extensively reviewed. Characterization of the starting materials, intermediates and the products by x-ray diffraction, thermogravimetry, brunauer–emmett–teller surface area analysis, and scanning electron microscopy are presented. Further, advantages and disadvantages associated with the digestion methods are discussed.

Recent advances in electrode material for symmetrical solid oxide fuel cells and way forward sustainability based on local mineral resources

“…The naturally occurring ilmenite mineral is being used as a starting material in the production of titanium-based products TiO 2 , which is well known for its photocatalytic activity, which includes water splitting and organic molecule degradation in particular. 215 The rutile and anatase crystal structures of TiO 2 improve thermodynamic stability, contributing to the composite material's good thermal and electrochemical stability by functioning as support or carrier, a membrane, and as the catalyst itself. 216,217 Electronic interactions of TiO 2 metal oxides with other materials can enhance electronic behaviour which contributes to lower CO-oxidation potentials and improve oxidation activity.…”

Fabrication of TiO2 Spheres and a Visible Light Active α-Fe2O3/TiO2-Rutile/TiO2-Anatase Heterogeneous Photocatalyst from Natural Ilmenite

“…Currently, titanium dioxide is produced from titanium ores by traditional processes such as the sulfate and chloride processes. , Globally, the sulfate process is employed in 40% of total TiO 2 production and the chloride process in 60% . In the sulfate process, low-grade ilmenite (40–60%, TiO 2 ) or titanium slag (72–85%, TiO 2 ) is digested in concentrated sulfuric acid at elevated temperature and pressure.…”

“…The resulting TiCl 4 vapor is liquefied and converted to titanium dioxide . The chloride process has advantages over the sulfate process, such as the production of high-purity TiO 2 , less environmental impact, and the generation of a limited amount of hazardous waste products. , Nevertheless, the requirement of high-purity TiO 2 ore for use in the chloride process was a significant hurdle due to the inability to produce pure TiO 2 by leaching ilmenite ore. To improve ilmenite sand purity, low-grade ilmenite ores were subjected to gravity and to magnetic and electrostatic separation processes. , In general, chloride and sulfate hydrometallurgical processes can be classified as (i) a smelting process followed by either sulfuric or hydrochloric acid leaching at elevated temperatures, (ii) reduction of ilmenite followed by acid leaching, (iii) diminution of the iron content in ilmenite by oxygen and ammonium chloride, (iv) oxidation of ilmenite followed by reduction of oxidized ilmenite and hydrochloric acid leaching, and (v) roasting and magnetic separation followed by hydrochloric acid leaching. , These extractive metallurgical processes involve multiple steps of energy and high-temperature treatments over 1000 °C, making them expensive . It is essential to develop an alternative process to produce high-quality TiO 2 from low-grade ores by minimizing and environmentally managing hazardous waste products.…”

Efficient Visible-Light Photocatalysis and Antibacterial Activity of TiO2-Fe3C-Fe-Fe3O4/Graphitic Carbon Composites Fabricated by Catalytic Graphitization of Sucrose Using Natural Ilmenite

“…Different solutions are used to extract titanium and iron from ilmenite such as hydrochloric acid, sulfuric acid, potassium hydroxide, and ammonium chloride. 16 Furthermore, preliminary techniques like ball-milling can enhance the dissolution in the above solvents. 17 Ilmenite sand has not been used widely, except to produce TiO 2 as the white color pigment and to fabricate novel photocatalysts including Fe 2 TiO 5 /TiO 2 18 and Fe 2 O 3 /Fe 2 TiO 5 /TiO 2 .…”

“…Ilmenite is found on beaches and hard rock deposits in countries including Australia, the USA, Brazil, India, Vietnam, and Sri Lanka, where their composition varies qualitatively and quantitatively. Different solutions are used to extract titanium and iron from ilmenite such as hydrochloric acid, sulfuric acid, potassium hydroxide, and ammonium chloride . Furthermore, preliminary techniques like ball-milling can enhance the dissolution in the above solvents .…”