Recycling permanent magnets for rare earths

On Technology Day this year, India’s first facility to produce rare earth permanent magnets was dedicated to the nation by Prime Minister Narendra Modi in Visakhapatnam. This plant, belonging to public sector Indian Rare Earths Ltd, is based on indigenous reduction-diffusion technology developed by the Bhabha Atomic Research Centre, and it produces samarium-cobalt (SaCo) rare earth permanent magnet and neodymium-iron-boron (NdFeB) permanent magnets. This is a big step in the technology journey of the country.

Why is the production of rare earth permanent magnets so important? These are essential for practically all electronics: Computers, laptops, mobiles, TVs, etc. These are also essential in automobiles (and even more so for electric vehicles), solar cells, wind turbines, defence, aerospace, etc. Military applications of permanent magnets include guidance systems for missiles and smart bombs, electric motors for ships and submarines, and sensors for surveillance and reconnaissance. In recent years there has been an increasing interest in the use of permanent magnets for new technologies like hypersonic weapons and directed energy systems. Predictably, the demand for permanent magnets has been growing exponentially.

Permanent magnets for the above-mentioned applications are made using rare earths. In the periodic table, there are 17 elements that comprise the rare earths. Compared to ordinary ferrous magnets, rare earth permanent magnets generate a very high magnetic field strength and large amounts of torque, making them ideal for applications requiring high-performance, compact and light-weight motors. Apart from unique physical properties the rare earths impart to magnets, they are peculiar also because they are found in few geographical concentrations in the world. China has over 90 per cent of the world’s share of rare earths.

A permanent magnet has nearly 30 per cent of rare earth by weight. For example, the amount of neodymium, one of the most sought-after rare earths, used for making permanent magnets, ranges from 29 per cent to 32 per cent by weight, depending on the application. The remaining is constituted by iron, boron, and small amounts of other rare earths. Another rare earth which is commonly used is dysprosium, which is particularly important for high-temperature applications. With growing requirements for permanent magnets, the demand for rare earths is also growing rapidly and is expected to grow in coming years as well.

The supply chain of rare earths is one of the biggest concerns of world leaders. China produces 90 per cent of the world’s neodymium and 99 per cent of the world’s dysprosium. The high concentration of rare earths in China gives it a huge strategic leverage. A taste of what a shortage of rare earths could mean was experienced by the world during Covid. Between 2020 and 2022, the prices of neodymium shot up more than three times, from $0.4 million a tonne to over $1.5 million a tonne. According to reports, in 2010, China unofficially banned the supply of rare earths to Japan over a territorial dispute relating to the Senkaku Islands.

It is in this context that setting up a production facility for permanent magnets in India is a significant step. Both NdFeB and SaCo permanent magnets, apart from commercial applications, have significant applications in the military. NdFeB permanent magnets, which will be produced in Visakhapatnam, can be used for motors, generators, actuators, and sensors, whereas SaCo permanent magnets are used in aircraft and missile guidance systems as well as in radars and sonars.

Like the rest of the world, India is an importer of rare earths. According to Statista in 2020, India’s import of rare earth amounted to 1,800 tonnes, about 0.67 per cent of the global figure. India’s share in the import of rare earths is modest, reflecting a low level maturity of its downstream industries like electronics, defence, and aerospace. However, as Make in India has made strides in these sectors, the demand for rare earths is expected to grow. When that happens, India will be heading for a strategic face-off with China, the biggest source of these materials.

Recycling magnets can be a cost-effective way to recover rare earth elements, including neodymium and dysprosium. Recycling permanent magnets will also reduce waste disposal in landfills and dependence on foreign sources. This will involve disassembly of electronic devices or end-of-life defence and aerospace equipment containing magnets and the extraction of rare earth elements from the magnet alloys. While India does not have the technology or recycling plant for permanent magnets, the US, Japan, Germany, China, and Canada have. Companies from friendly nations can be incentivised to set up recycling facilities in India as a win-win proposition, while efforts to develop indigenous technology are taken up simultaneously.

According to a report of the United Nations University, India generated 3.2 million tonnes of e-waste in 2019, making it the third-largest in the world on this. The e-waste generated is expected to increase to 5.2 million tonnes by 2025. In future, India will also have significant solar waste, given the growth of solar plants in India. By 2050, solar e-waste is expected to grow to 1.8 million tonnes. Similarly end-of-life defence and aerospace equipment also generates significant e-waste. The weight of permanent magnets in a computer and mobile phone varies from around 0.1 per cent to 1 per cent, depending on functionalities and specifications. Assuming an average of 0.5 per cent of e-waste is permanent magnets, around 20,000 tonnes of permanent magnets in India go unrecycled in Indian e-waste. The weight of rare earths in these magnets would be around one-third, i.e. about 6,000 tonnes, much more than the quantities imported currently. Even a fraction of e-waste would be substantial for the country’s rare earth requirements.

E-waste collection and recycling in India, however, suffer from several institutional and management weaknesses. Reportedly, only about 22 per cent of the e-waste generated is collected. The recycling technology employed is primitive and it is mostly about scavenging precious metals like gold and silver. Improving e-waste collection requires behavioural change in society and with Digital India becoming ubiquitous, e-waste is generated in the remotest of villages. The Swachh Bharat campaign could help create a mindset change. Defence and aerospace are also sitting on piles of end-of-life equipment, which contain a huge quantity of permanent magnets. These readily available permanent magnets should be recycled to produce rare earths. It is important not to treat a recycling plant on traditional economic considerations. The environmental benefits should also be considered.

A permanent recycling plant for rare earths is a backward integration step for the Visakhapatnam facility because it will produce rare earths the plant will need. More importantly, it is a must for strategic independence, something which is non-negotiable. 

The writer is former defence secretary and distinguished visiting professor, IIT Kanpur