‘There are no dedicated battery recycling facilities set up in South Africa so we are losing valuable materials like lithium and cobalt,’ says Lesego Siwela, applications engineer at Cwenga Technologies. The South African company is one of the first players trying to fill the country’s gap in recycling potential.
Cwenga Technologies realises chromatographic separation of battery metals via leaching using reusable and low-cost reagents at room temperature and at atmospheric pressure. The ‘eco-friendly’ process has long been used in water purification and is therefore ‘commonly in stock’ across South Africa. The solution was fine-tuned with support from the University of the Western Cape.
The recycler supplies ion exchange resin and activated carbon with input materials sourced from industry partners Lanxess and Chemviron. The cobalt is extracted via ligand exchange while nickel extraction can be best achieved with chelating resins.
‘Both approaches are highly selective for specific metals and, by combining them, we can reclaim all of them,’ Siwela explains. ‘At our in-house lab, we can analyse the samples and deliver material at lab scale as well as pilot-scale. Provisional patents have been filed and we are working on expanding this to full commercial scale.’
Her team is also installing a new crusher with protective housing so that no gases, fumes or smoke escape the process thereby minimising the risk of fire.
New market data suggests the South African battery market will be worth an estimated US$ 965 million (EUR 928 million) this year. Market analysts expect it to reach US$ 1.7 billion by 2030, representing a compound annual growth rate of 7.7%.
In terms of chemistry, the lead-acid battery is witnessing the highest growth due to expanding applications in uninterrupted power supply (UPS), transport vehicles, automotive, telecommunication and electric bikes. The ‘mounting investment’ in electric vehicle markets, owing to the high demand for vehicles in both developed and developing nations, is also likely to result in a higher adoption of lithium-ion batteries in the next few years.
Further growth drivers include the demand for portable electronics such as tablets, LCDs, smartphones and wearable devices as well as stricter emission standards required by developed countries, coupled with rising attention to fuel efficiency.
However, Mintek, South Africa’s national mineral research organisation, laments that the nation’s low collection rates and little infrastructure makes lithium-ion battery recycling a very challenging business case. This sector is seen as viable once recyclers reach a national processing capacity of 500 tonnes per year.
As yet, the figure is thought to be below 10 tonnes. Leveraging existing recycling technologies is seen as vital to scaling up.
‘Our approach addresses the high costs that come with battery recycling,’ Siwela says. ‘In many parts of the world, not just Africa, battery recycling is so expensive it is hardly viable. It’s a tough niche to be in.’
Eager to grow the business, Cwenga has acquired a stockpile of batteries to work with and these are now being detoxified and discharged. Siwela points out that the company has successfully used its approach for commercial-scale copper refining during the past 20 years. ‘We’re now building on this and expanding it to specifically cater to the rapidly growing battery market.’
Another benefit is that the resins can last up to five years because the reagents don’t destroy them. ‘This shows you can create a high-quality product at a competitively low cost,’ Siwela concludes.