Chromium and the Interpretation of Vanadium-Containing Resin for General Public Understanding

The chemical symbol of vanadium is V, its atomic number is 23, and its relative atomic mass is 50.9415. It was first discovered by Spanish chemist De Leo in Mexico when he was studying "brown lead ore" in 1801, but it was not recognized by the academic community at that time. In 1830, Swedish scientist Sefstrom independently rediscovered this element during the process of refining ductile iron and named it Vanadium (translated as "钒" in Chinese). In 1867, British chemist Roscoe reduced vanadium dichloride with hydrogen and successfully produced pure metallic vanadium for the first time. 
Vanadium is a shiny silver-gray metal with a relative density of 6.11 g/cm³ at 19℃. Its melting point is as high as 1917℃, and its boiling point is 3421℃. It is a rare metal with a high melting point. Pure vanadium is hard, non-magnetic, and has ductility. 

In terms of chemical properties, vanadium belongs to the same group as tantalum and niobium and is a moderately reactive metal. The common oxidation states of vanadium include +2, +3, +4, and +5, among which +5 is the most stable. Vanadium ions in different oxidation states exhibit different colors in aqueous solutions (light purple, green, blue, and yellow), which is the reason for the rich colors of vanadium compounds. The compounds of pentavalent vanadium are oxidizing, while those of lower valence are reducing.

The core pain points faced by the traditional vanadium extraction process 
1.The process flow is lengthy and complex.
The traditional sodiumization roasting process involves multiple steps such as roasting, water leaching, acid precipitation, alkali dissolution, and ammonium salt purification. The procedures are cumbersome and the operating conditions are strict, making it difficult to ensure the continuity and stability of production. 
2. The recovery rate of vanadium resources is generally low.
Due to technical limitations, the recovery rate of vanadium from lignite is usually less than 45%. A large amount of valuable metals are not effectively extracted, which not only leads to a serious waste of precious resources but also directly increases the raw material cost per unit product. 
3. Severe environmental pollution and energy consumption pressure
The production process consumes a large amount of sodium salt and sulfuric acid, and emits sulfur-containing exhaust gas, ammonia nitrogen wastewater and solid waste. The cost of environmental governance is high, and this high-energy and high-emission mode is contrary to the green and low-carbon development trend. 
4. Product purity and added value are limited. The traditional production process results in a high content of impurities in the crude vanadium. It requires complex refining to meet the demands of high-end applications, which leads to low product value and weak extension capabilities of the industrial chain, making it difficult to meet the needs of high-end manufacturing.