Cradle to Gate
Identity ID
a216d4e2-5e2d-4d50-8b91-f2881be5a2fd
Materials
Associated ID
7e373adb-ae40-4222-9f61-6705a9c2a775
Included activities starts
Included activities ends
Description
This dataset represents a product that is ammonium paratungstate (APT), an inorganic compound product prepared from tungsten concentrate via a hydrometallurgical process. Its appearance is small transparent monoclinic crystals or white crystals, with a relative density of 2.3; it is readily soluble in water, insoluble in ethanol, and its aqueous solution is weakly acidic. Ammonium paratungstate has a relatively high tungsten content and good thermal-decomposition characteristics; under heating it can decompose to generate tungsten trioxide, and metallic tungsten can be further prepared through a reduction process. This product has high purity and low impurity content, and is the core key raw material for preparing tungsten powder, tungsten carbide and various other tungsten-based products, occupying a core pivotal position in the tungsten smelting and tungsten deep-processing industrial chain. The upstream raw material of this product is tungsten concentrate, and the downstream is widely applied in tungsten powder preparation, cemented carbide production, tungsten-based functional material processing, metallurgical additives and other tungsten-industry deep-processing fields; it is an important chemical intermediate that links the upstream and downstream of the tungsten metallurgy industrial chain. 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
Ammonium paratungstate (APT) is prepared using tungsten-cobalt alloy waste and tungsten concentrate as the main raw materials, using advanced energy-saving and environmentally friendly hydrometallurgical processes. The production process includes raw material pretreatment, roasting, ball milling, alkali boiling and decomposition, filtration and washing, ion exchange purification and evaporation crystallization.
Process Description
Ammonium paratungstate is an inorganic compound with the appearance of monoclinic fine transparent crystals or white crystals. Relative density 2.3. Soluble in water, insoluble in ethanol. The aqueous solution is slightly acidic. APT has a high tungsten content and good thermal decomposition characteristics. When heated, it can decompose to form tungsten trioxide, which can then be reduced to obtain metallic tungsten. Therefore, it is a key raw material for the preparation of tungsten powder, tungsten carbide and other tungsten products. It has high purity and few impurities, and occupies a core position in the tungsten smelting and deep processing industry chain.
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
Ammonium paratungstate (APT) is prepared using tungsten-cobalt alloy waste and tungsten concentrate as the main raw materials, using advanced energy-saving and environmentally friendly hydrometallurgical processes. The production process includes raw material pretreatment, roasting, ball milling, alkali boiling and decomposition, filtration and washing, ion exchange purification and evaporation crystallization. First, the crushed raw materials are sent to an electric shuttle furnace and roasted at 825 to 850°C for about 3 hours to convert tungsten into tungsten trioxide. After the roasted material is refined to more than -320 mesh by wet ball milling, it is decomposed by alkali boiling with sodium hydroxide solution to generate a soluble sodium tungstate solution. After plate and frame press filtration and multi-stage washing, the filtrate is combined to form a high-concentration sodium tungstate solution (pre-exchange solution). Subsequently, sodium tungstate is converted into a high-purity ammonium tungstate solution through the anion exchange process in the steps of adsorption, washing, desorption and column washing. Finally, after removing molybdenum and purifying the ammonium tungstate solution, it is sent to the crystallization pot for evaporation and crystallization by steam heating to obtain high-purity ammonium paratungstate (APT) product.