The Adaptive Sponge Absorbs Phosphate from Contaminated Waterways
Phosphates found on the earth’s crust are an essential element for aquatic plants and animals to thrive. However, most of them flow into the waterways due to man-made activities.
This has resulted in algae blooms that have covered some lakes and rivers, depriving marine organisms of the oxygen needed to survive. A new sponge material has helped scientists tackle the problem by not just soaking the phosphate content but also collecting it for reuse.
Phosphate is a common chemical found in fertilizers and also found in pet and wildlife manure. Because of human activities, much of the phosphate content has entered the water stream, contaminating rivers and other waterways that give rise to algae blooms.
A team of scientists from Northwestern University has researched to solve this global issue with the new material called Phosphate Elimination and Recovery Lightweight (PEARL) membrane. It is a flexible and sponge-like material that is covered in nanostructures to bind phosphate ions.
It can collect 99% of the phosphates found in polluted water. By balancing the pH levels of the material, the sponge releases the collected phosphates and makes it reusable.
These features were demonstrated in the lab with actual water samples collected from waterways in Chicago. The sponge proved to be effective in different water quantities – ranging from milligrams to kilograms.
This technology is way more efficient in cleaning phosphates from polluted water bodies than current ones – which are costly, complicated and generate waste.
One of the biggest achievements of this research is that it has not only solved the pollution problem but also created a sustainable and circular economy. By extracting the phosphate collected, scientists can reuse the phosphate and also the sponge for river cleanups.
The PEARL membrane is an upgraded version of a previously developed sponge by the same team, to remove oil from polluted water. By changing the nanostructures, the team hopes that it would clean and tackle multiple pollutants at the same time – linking it as a potential Swiss Army knife for pollution solution.