From waste to resource: Plants yield new precision separation technologies

There’s a reason why the old-time prospectors checked gum leaves for gold. It’s the same reason scientists are looking to plants for new circular economy solutions. Membrane separation mechanisms turn waste into a resource.

Plants are incredibly tolerant to environmental challenges, developing survival adaptations over millions of years to extract, separate and store minerals, metals and contaminants from the soil. Their cell membrane components can identify specific molecules, separate them from their surroundings and transport them to their desired location. Plants compartmentalise their resources.

And that’s precisely what’s needed in mineral extraction and water purification.

Researchers at the Australian National University (ANU) have been studying these inherent separation processes for crop engineering applications in Australia, like drought resilience and salt tolerance.

Now this research is being used in new wastewater recycling technologies to clean water and harvest valuable metal, mineral and scarce nutrients.

It’s estimated that global wastewater contains three million tonnes of phosphorus, 16.6 million tonnes of nitrogen and 6.3 million tonnes of potassium. The recovery of these nutrients could offset 13.4 per cent of global agricultural demand for these resources. The ammonia and hydrogen also locked away in this messy mix of wastewater could power 158 million households – but only if these molecules can be purified.

Advances in precision separation technology could also provide flood and drought-prone communities across Australia with reliable access to clean drinking water.

“Clean water and the security of nutrient resources underpin agricultural productivity. Development of technologies to sustainably manage these resources is essential for food security in Australia and globally,” said ANU plant scientist Dr Caitlyn Byrt.

“It’s hidden in plain sight. Nature has already solved issues related to managing those sorts of resources. Once understood, billions of years’ worth of accrued evolved biological capability can be applied to new technologies,” Dr Byrt concludes.

Read more of the Winter 2023 edition of CropLinks here: CropLife Australia | CropLinks Winter 2023