Adsorbents based on iron hydroxide for the remediation and restoration of lakes


The eutrophication of lakes is one of the most common water quality problems worldwide. The use restrictions accompanied with eutrophication for example drinking water extraction, fish farming or swimming often lead to efforts to improve the situation.
An excessive availability of phosphorus in the water and sediment is seen as the main reason for increased biomass production and thus the eutrophication in water. Phosphorus, however, also represents the limiting factor for eutrophication, i.e. a controlled reduction in the concentration of plant-available phosphorus can effectively limit eutrophication.
A very effective way to eliminate phosphorus is binding it on the surface of iron hydroxide particles. To meet the different requirements regarding the treatment technology a range of products under the name “FerroSorp® GW” has been developed, which can be realized in in-situ and ex-situ processes for the elimination of phosphate.


In a first step in water dissolved phosphate ions are adsorbed onto the surface of FerroSorp® GW. In a subsequent reaction the conversion to stable iron phosphate occurs according to the following equation:

The product range

FerroSorp® GW is available in the following standard grain sizes:


Depending on the grain size following applications for FerroSorp® GW are recommended:

Examples for application variants

Advantages at a glance

In comparison with iron or aluminum salt solutions

Brochure FerroSorp® GW [140 KB]