Indium (In): ITO Target Production, Medical Imaging Agent, and Liquid Metal Alloy Formulation

Indium is a metallic element with the chemical symbol In and atomic number 49, belonging to Group IIIA in the fifth period of the periodic table. In its pure form, it appears as a silvery-white metal with a slight bluish tint. This extremely soft metal can be scratched with a fingernail. It exhibits excellent plasticity and ductility, allowing it to be pressed into thin sheets. Indium has a melting point of 156.61°C, boiling point of 2060°C, and density of 7.30 g/cm³. In its liquid state, indium can wet glass surfaces and tends to adhere to contacted surfaces, leaving black marks.

Applications

1. Primary use: Production of ITO (indium tin oxide) targets for displays.
2. Medical imaging: Indium colloids for liver/spleen/bone marrow scans.
3. Liquid metal alloys: Forms fusible alloys with gallium (e.g., Galinstan).

Product Series

Health and Safety Information

Packaging Specifications

• Standard packaging: 50 kg/drum, 500 kg/pallet, ton bags
• Sample packaging: 500 g/bag, 1 kg/bottle

About Indium

Indium is primarily extracted through the extraction-electrolysis method, which currently serves as the mainstream production technology worldwide. The basic process flow is as follows: indium-bearing raw materials → enrichment → chemical dissolution → purification → extraction → back-extraction → zinc (or aluminum) displacement → sponge indium → electrolytic refining → refined indium. Approximately 90% of the world's indium output comes from by-products of lead-zinc smelting plants. The primary methods for indium recovery involve concentration from flotation residues, slags, and anode slimes generated during copper, lead, and zinc smelting. Depending on the source and indium content of the recovered materials, different extraction processes are employed to achieve optimal efficiency and maximum yield. Commonly used techniques include oxidative slagging, metal displacement, electrolytic enrichment, acid leaching-extraction, extraction-electrolysis, ion exchange, and electrolytic refining. Currently, the most widely applied method is solvent extraction, recognized as a highly efficient separation and recovery process. Notably, ion exchange methods for indium recovery have not yet been reported for industrial-scale applications. During separation from less volatile elements like tin and copper, indium predominantly concentrates in flue dust and slag residues. Conversely, when separated from more volatile elements like zinc and cadmium, indium becomes enriched in furnace slags and filter residues.