High-efficiency Internal Reuse of Raffinate in Vanadium (V) Extraction Industry and the Research of Intensifying Leaching Mechanism

ABSTRACT

The current fluorine wastewater treatment method mainly relies on neutralization, which has the drawback of high alkali consumption, solid waste generation, and re-dissolution of heavy metals. Similar problems exist in the vanadium (V) industry. This study aims to minimize fluorine wastewater generation, reducing CaF₂ consumption by internally reusing raffinate at certain stages of the V extraction process. In the raffinate reuse leaching process, Al-F complex in the raffinate is decomposed and HF is produced under the action of sulfuric acid. This enhances the destruction of muscovite and improves the leaching efficiency of V. Response surface methodology (RSM) was used to optimize the raffinate reuse leaching process, and when the CaF₂ dosage was reduced from 3 wt.% to 1.8 wt.% and the H₂SO₄ concentration was as low as 14 vol%, the process maintained the optimal V recovery efficiency of more than 86%. This methodology can achieve a 100% reuse rate of the raffinate, and has great potential for its application in the vanadium leaching industry.

KEYWORDS:

• Vanadium
• raffinate
• internal reuse
• fluoride wastewater

Highlights

• The process and mechanism of internal reuse of raffinate to leaching V were studied.

• The raffinate reuse leaching process abated fluoride contamination.

• The optimal parameters of the raffinate reuse leaching process are obtained by the RSM.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed on the publisher’s website.

Additional information

Funding

This work was financially supported by the National Key R&D Program of China (2018YFC1900602), the Project of National Natural Science Foundation of China (No.51774216), and the Outstanding Young and Middle-aged Science and Technology Innovation Team Project of Hubei Province (T201802).