Innovative project tackles phosphorus in waterways

Over the past year, the two organizations have been working on a cutting-edge project called “Removal of Phosphorus from Surface Water Using Seamless Capsules in the Form of an Iron/Alginate Hydrogel Biocomposite”.

Phosphorus can lead to issues such as harmful algal blooms and deteriorating water quality. To address this, the project uses innovative iron-alginate hydrogel capsules that absorb phosphorus from contaminated water. Unlike traditional methods, these capsules are made using iron (Fe3+) instead of calcium (Ca2+), making them stronger, less prone to swelling, and more porous—ideal for absorbing contaminants.

“The capsules not only target phosphorus but also capture heavy metals like lead, copper, and cadmium, further cleaning the water. Once they have absorbed the phosphorus, the capsules can be repurposed as a fertilizer for private gardens, releasing nutrients over time when exposed to light,” says Christian Vogelsang, senior researcher in NIVA. 

However, the fact that the capsules also capture heavy metals can be a challenge when they are to be reused as fertilizer, as the heavy metals may also be released into the environment.

The project was co-financed by the Norwegian Financial Mechanism 2014-2021, and NIVA was primarily assisting in quality assuring the work done by our Polish partners.

For those interested in learning more about this innovative approach to water purification and its potential benefits for plant growth, more information can be found on APRS' website.