Rare earth is the general name for the 15 lanthanide elements in the periodic table of elements 57-71, plus scandium 21 and yttrium 39, which have similar properties to them, for a total of 17 elements.
Rare earths are divided into light rare earths and heavy rare earths: light rare earths include: lanthanum, cerium, praseodymium, neodymium, promethium, samarium, and europium. Heavy rare earths include: gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, and yttrium. Due to their strong role and low usage, rare earths have become an important element in improving product structure, increasing scientific and technological content, and promoting technological progress in the industry. They are widely used in the fields of metallurgy, military, petrochemical industry, glass ceramics, agriculture, electronics and new materials.
What many people don’t know is that even if the United States mines rare earths, they have to be sent to China for processing. In 2019, the output of rare earth ore in the United States was 26,000 tons, of which 19,353 tons were sold to China, accounting for 74%.
Many people say that the United States does not process rare earths to protect the environment. In fact, this is not the case. The real reason is that the purification and separation technology of rare earths has been monopolized by China.
How difficult is rare earth separation and purification technology?
We must know that the most difficult thing about rare earth minerals is not mining, but extraction, separation and purification. Xu Guangxian, the father of China's rare earths, , carefully designed a set of chemical operation procedures, and derived a corresponding set of cascade extraction theoretical formulas. On this basis, he designed a new reflux cascade extraction process, which increased the purity of rare earth separation to a world record of 99.99%. Using this new process, the originally complex rare earth production process was completely simplified. Since then, my country's rare earth separation technology has begun to be at the forefront of the world, fundamentally changing the embarrassing situation of being controlled by others.
China is the world's largest rare earth smelting and separation country, and 62% of its rare earth companies are separate smelting companies. In 2018, China's output of smelting separation products was 145,800 tons, accounting for 85.83% of the global total supply.
A series of technologies such as "new technology for integrated green and efficient leaching and extraction of ionic rare earth raw ores", "new technology for low-carbon, low-salt, ammonia-free nitrogen separation and purification of rare earths", and "4N ultra-high purity rare earth metal integrated preparation technology" are all original.
Moreover, we have proposed and developed an original technology for the saponification, extraction, separation and precipitation of high-purity magnesium bicarbonate solution to recover rare earths. For the first time, the magnesium chloride wastewater and CO2 gas generated during the rare earth separation and purification process are recycled at low cost for continuous carbonization and large-scale preparation of pure magnesium bicarbonate solution, replacing liquid ammonia , liquid alkali , ammonia bicarbonate, etc. for rare earth extraction, separation and precipitation.
In addition, China has studied a variety of environmentally friendly technologies for the purification and separation of rare earths. Professor Li Mei’s team has developed a technology for the extraction of high-purity single rare earth compounds and a preparation process for large particle rare earth compounds. A series of scientific research results such as "", adopts a new process of first decomposing bastnaesite and then alkali dissolving monazite, which greatly reduces the amount of alkali. At the same time, the associated elements fluorine, phosphorus, and thorium are recovered in the process of extracting rare earths. Fluorine is recovered with sodium fluoride, and phosphorus is recovered with trisodium phosphate . This enables China's light rare earth extraction and separation technology to say goodbye to three wastes pollution.
China monopolizes rare earth technology
Since 2011, China’s annual rare earth patent applications have exceeded the rest of the world combined. Compared with the rest of the world, China’s application pace is accelerating—a 250% increase from 2011 to 2018. Chinese companies can use legal tactics such as patent litigation and patent blocking to undermine or invalidate existing non-Chinese patents. Meng Qingjiang, executive deputy secretary-general of the Jiangxi Rare Earth Society, once said proudly: "Rare earths mined abroad can only be sent to China."
Therefore, the United States does not have a purification and separation system. It is not environmentally friendly, but it does not have this technology. From rare earth mining, smelting and separation to magnetic materials processing, the United States does not have relevant technical reserves in the entire industry chain. According to a report on rare earth materials released by the U.S. Government Accountability Office in 2016, it may take 15 years for the United States to establish a domestic rare earth supply chain.
In fact, as China monopolizes rare earth technology, China has been reducing the mining of rare earth mines in China over the years. Instead, it has turned to importing rare earth ores and engaged in the rare earth processing industry, that is, importing rare earth ores from foreign countries, then refining them, and finally exporting rare earth products
Before 2014, China usually accounted for more than 85% of global rare earth mining. In the following years, there was a more obvious downward trend. In 2015 and 2016, the above proportion was slightly more than 80%. In 2017, it was less than 80%. In 2018, it dropped to 63.16%. In 2019, it continued to shrink to 60%. By 2020, my country's global rare earth production proportion has dropped to 58.33%.
With China's sharp production reduction and China's certain restrictions on the export of rare earths to the United States, the United States can only increase the mining of domestic rare earth ores. In 2020, the production of rare earths in the United States increased significantly to 38,000 tons. Although it is still far lower than China, its global share has increased to 15.83%, ranking second in the world. Although the United States has increased its mining of rare earths, it can only transport semi-processed rare earth ores to China for processing.
