FerroSorp® Plus

Granular iron hydroxide for effective removal of water contaminants


Iron (III) hydroxide, due to its chemical activity, is highly suitable for binding arsenate, phosphate and sulfide ions in aqueous media. The technical application of this universal absorbent failed in the past because of its usual paste-like appearance which prevents the use in simple filtration columns. Using a patented process, we were able to manufacturer iron (III) hydroxide in granular form. A wide range of grain sizes can be produced through a combination of grinding and sieving, which gives access to a variety of new applications.

Prospektbild - FerroSorp® Plus | HeGo Biotec

Electron microscope image of FerroSorp® Plus grains


The first step is the absorption of in-water dissolved arsenate and phosphate ions to the surface of FerroSorp® Plus. In a consecutive reaction, the conversion to stable iron arsenate and iron phosphate takes place. The removal of sulfide ions is carried out by forming insoluble iron sulfide. Besides ordinary heavy metal ions, such as lead, copper and zinc, other contaminants like antimony, molybdenum, cadmium, selenium, uranium and fluoride are bound as well. In addition, a very non-specific binding of dissolved organic water pollutants by way of absorption is possible. The following chemical equations show the reaction of iron hydroxide with phosphate, arsenate, and hydrogen sulfide in a simplified scheme:


At the present time, FerroSorp® Plus is suitable for:

  • Removal of arsenic(III)- and arsenic(V)-ions in potable water treatment
  • Cleaning of rainwater run-off, e.g. in retention soil filter systems
  • Binding of phosphate during water restoration (Video) 
  • Treatment of contaminated groundwater during the remediation of contaminated sites
  • Further phosphorus elimination in the clear water discharge of small sewage treatment plants and constructed wetlands
  • Pollutant retention in “reactive barriers”
  • Nutrient absorption in aquarium and garden pond maintenance
  • Treatment of heavy metal polluted industrial waste water

Testing facility

For technical tests using granular iron hydroxide FerroSorp® Plus, a testing facility with multiple absorption columns and an optional upstream turbidity remover is available.

ferrosorp-plus-testanlage_englAdvantages at a glance

  • Safe procedure tested and used for decades
  • High cleaning performance at low cost
  • High loading rates due to simultaneous regeneration
  • High activity levels of the absorption pellets guarantee a high-level of purification
  • Low pressure drop across material due to optimized pellet shape
  • Easy and cost-effective disposal of spent material by return guarantee of the supplier