Nov 07, 2022 08:00:00

Technology will be developed to make mining of rare earths cleaner than before, which can adversely affect the global environment

Electric vehicles, wind turbines, and LED lighting, which have become commonplace in modern society, are said to be environmentally friendly, but they are said to cause environmental pollution when they are manufactured. Therefore, a group led by Mr. Gaofeng Wang, a Chinese scientist, announced an approach called 'electrokinetic mining' as a new technology for mining rare earth elements called rare

earths , which are raw materials.

It's electric! Technique could clean up mining of valuable rare earth elements | Science | AAAS
https://doi.org/10.1126/science.adf6050

The magnets in motors and generators that are frequently used today, as well as the light-emitting parts of LEDs and liquid crystals, depend on rare earths, and when mining rare earths, eluents such as ammonium sulfate , which contaminate soil and groundwater, are required. I'm here. In addition, a large area of land is required for waste disposal.

About 80% of the world's heavy rare

earth supply comes from areas adjacent to southern China and Myanmar, where environmental regulations are poorly enforced and illegal mining is common.

Gaofeng Wang and colleagues from the Guangzhou Institute of Geochemistry, Chinese Academy of Sciences have devised electrokinetic mining as a cleaner alternative to traditional mining methods that lead to environmental pollution. The way it works is that electrodes at the top and bottom of a bulk soil induce an electric field that speeds up the movement of the eluent and the ions it extracts. 'It has real potential to outperform conventional mining techniques in terms of environmental impact and economics.'

Gaofeng Wang and his group started with laboratory tests, scaled up to 20 kg of material, and then tested 14 tons of clay chunks in a real ion adsorption deposit .

These tests are faster and have less environmental impact than conventional mining methods, and are estimated to cut mining costs by about a third, according to British rare earth expert Gareth Hatch. , said it 'doesn't know yet' if the technology can be scaled up.

As a next test, Gaofeng Wang and his colleagues will contract with a major rare earth supplier to try to optimize operating conditions with about 2,000 tons of soil.

Henning Prommer, an environmental engineer at the University of Western Australia, Perth, points out that ``electrokinetic mining has environmental impacts, just like traditional mining methods. Given the extremely important role that rare earths play for us, we welcome the reduction in the environmental impact of mining.'