Vivianite precipitation for iron recovery from anaerobic groundwater

Research output: Contribution to journalArticleScientificpeer-review

1 Citation (Scopus)
12 Downloads (Pure)

Abstract

Iron in anaerobic groundwater is commonly removed by oxidation followed by sand filtration. This produces large volumes of iron(III)(hydr)oxide sludge with little value. Our research investigates the novel concept of anaerobic iron(II) recovery from groundwater as the valuable mineral vivianite (Fe3(PO4)2 • 8 H2O) by the addition of phosphate to the water. We found that vivianite precipitated both in synthetic and natural groundwater when the saturation index (SI) was higher than 4. The SI can be increased by elevating the pH, which allows for iron removal at lower concentrations. Anaerobic iron removal reached 93.7% in natural groundwater, which increased further to 99.9% after a subsequent aeration step. Vivianite precipitation followed second order kinetics with a rate constant of 2.3 M−1s−1 and the sludge volume decreased by two third compared to iron oxidation. We therefore conclude that anaerobic iron removal is a promising new approach towards sustainable groundwater treatment.

Original languageEnglish
Article number118345
JournalWater Research
Volume217
DOIs
Publication statusPublished - 2022

Keywords

  • Drinking water
  • Groundwater
  • Iron
  • Treatment
  • Vivianite

Fingerprint

Dive into the research topics of 'Vivianite precipitation for iron recovery from anaerobic groundwater'. Together they form a unique fingerprint.

Cite this