Two young South Africans are among the 16 engineers hailing from seven countries in Africa, who have been chosen for the shortlist of the prestigious Africa Prize for Engineering Innovation.
University of the Witwatersrand chemical engineering research fellow Collins Saguru has developed AltMet, an economical, environmentally sustainable process to recover and reuse precious metals found in the autocatalytic converters of petrol and diesel vehicles.
“This recycling process addresses the demand for precious platinum group metals (PGMS) in a way that is profitable and environmentally sustainable,” he said of his invention.
An autocatalytic converter reduces the toxicity of gases emitted by vehicles’ exhaust pipes and contains PGMS, which are valuable and useful for industrial processes. PGMs are also on the European Union’s critical materials list.
Saguru dismantles used autocatalytic converters, crushes and leeches them before extracting the PGMs. Aluminium and cerium are also extracted during this process.
While other recycling methods exist, it requires high heat. Saguru’s method uses much lower temperatures, which makes the process more affordable and emits fewer toxic gases. His process uses chemical reagents, which are cheap, relatively common and environment-friendly.
Meanwhile, nuclear physicist Shalton Mothwa has been recognised for his Aeon Power Bag invention, which allows users to charge their phones and tablets on the go by converting radio or telecommunications waves and solar energy into power.
The lightweight backpack contains a unit that harvests radio waves in the surrounding environment and converts them to electricity. When radio signals are low, the solar charging unit kicks in. The bag is also capable of inductive charging when placed against an inductive charging power mat – increasingly found in airports and restaurants.
“The power bag could make the lives of people with limited access to electricity much easier,” Mothwa highlighted.
The energy generated is stored in a battery, similar to a power bank, and the user can charge their devices anywhere, anytime by plugging in to the unit using a USB cable.
The battery pack charges in under 90 minutes when the radio wave, solar and inductive units are working at their optimum.
The Aeon Power Bag is made from locally sourced renewable and reusable materials.