Current status of vanadium resources and research progress on vanadium extraction with organic phosphorus extractants

Vanadium is an important additive that is used widely in modern industries, as well as an important strategic metal. Vanadium metal elements, compounds, and alloy materials have unique and valuable properties, which have enabled great advances in the world’s industries, particularly in steel, chemical, medical, petroleum, nonferrous metals, energy, construction, environmental protection, and nuclear. China not only has one of the world’s largest vanadium resources but is also the largest producer and consumer of vanadium, occupying an important position in the international market. Vanadium is a rare and precious metal and is prodigiously dispersed in the earth’s crust. There are only a few independent vanadium minerals. China’s vanadium resources are mainly found as vanadium–titanium magnetite and stone coal. In recent years, the extraction of vanadium from stone coal has become an important project in the development of vanadium resources in China. This article introduced the main reserves and distribution channels of global vanadium resources and their market supply, demand, and application status. The focus is on the central structure of organophosphorus extractants, effective groups and steric effects, and the mechanism of synergistic extraction of vanadium via ion exchange, as well as the development and application of new phosphorus extractants for vanadium extraction. Research and development of phosphorus-based extractants, application of new processes, and collaborative extraction are currently the main research directions of phosphorus-based extractants for vanadium extraction. This article analyzed vanadium extraction mechanisms of different extraction systems using acidic phosphorus extractants, neutral phosphorus extractants, and other new phosphorus extractants. The analysis shows that the loss of the organic phase, steps of extraction and stripping of vanadium, extensive extraction and separation times, and occurrence of emulsification are common difficulties currently associated with the extraction of vanadium. Therefore, it is necessary to continuously develop new and efficient extractants, develop clean and green extraction technologies, use synergistic effects based on the original extractants, explore new combinations of extractants, and better promote the development of China’s vanadium industry.