Cradle to Gate
Identity ID
471fb9be-3d9d-48ab-9532-d5c0c8b18e2e
Materials
Associated ID
ee4daab2-0047-4be2-bc0a-300476959e1d
Included activities starts
Included activities ends
Description
This dataset represents a product that is tellurium powder, a high-purity industrial tellurium product with a tellurium grade of ≥99%, in the form of a grey powder, with silvery-white crystals, and a highly toxic chemical substance. Its physical characteristics are a density of approximately 6.25 g/cm³, a melting point of 452℃ and a boiling point of 1390℃; its chemical characteristics are that it is insoluble in water and carbon disulfide, soluble in sulfuric acid, nitric acid and alkaline solutions, and has semiconductor properties and a photoelectric effect. The upstream raw material of this product is tellurium-precipitation tailings, which are purified and prepared via a tellurium-refining process, and the downstream is widely applied in semiconductor-device manufacturing, alloy production, chemical synthesis and other fields; it is also the core basic raw material for preparing various tellurium compounds. The dataset includes the main raw and auxiliary materials, energy and wastes in the production process; infrastructure such as the manufacture of production equipment and plant construction is not included within the boundary of the dataset; the data inventory is formed by merging data from multiple sources.
Activity Description
Tellurium refining includes processes such as ball milling of refining slag, leaching, neutralization and tellurium precipitation, dissolution of tellurium dioxide, reduction, deselenization with sodium sulfite, oxidation, solution preparation, tellurium electrowinning, tellurium melting and casting, and waste liquid treatment, covering the entire process from tellurium precipitation tailings to tellurium powder.
Process Description
Tellurium powder (Te) is a highly toxic gray powdery chemical substance with a grade of ≥99%, a density of about 6.25 g/cm³, a melting point of 452°C, and a boiling point of 1390°C. Its crystals are silvery white, insoluble in water and carbon disulfide, but soluble in sulfuric acid, nitric acid and alkaline solutions. The upstream raw material of tellurium powder is precipitated tellurium tailings, which is purified and prepared through the tellurium refining process. It has semiconductor properties and photoelectric effects. It is commonly used in the fields of semiconductor devices, alloy production and chemical industry. It is also a key raw material for the preparation of tellurium compounds.
Time period
2021
2026
Geography
China
Geography comment
Generated by merging multiple data sets in this geographical location.
Macroeconomic value
Business-as-Usual
Data validation
Yes
Technology
Current Technology
Technology comment
Tellurium refining includes refining slag ball milling, leaching, neutralization and precipitation of tellurium, dissolution of tellurium dioxide, reduction, sodium sulfite deselenization, oxidation, solution preparation, tellurium electrowinning, tellurium melting and casting, waste liquid treatment, etc. The process is as follows: after the refining slag is refined by wet ball milling, it is heated and leached with sodium hydroxide solution to allow tellurium to enter the solution; the leachate is neutralized to precipitate tellurium to produce crude tellurium dioxide, which is then dissolved with hydrochloric acid and reduced by introducing sulfur dioxide to obtain crude tellurium; after the crude tellurium is calcined to remove residual selenium, it is electrowon in an alkaline medium to obtain high-purity electrowon tellurium powder.