Difference between revisions of "Iron filings (ZVI)"

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===How is it being used?===
 
===How is it being used?===
 
No projects that use ZVI were found in Ontario.  
 
No projects that use ZVI were found in Ontario.  
[[File:Screenshot 2025-08-13 113919.png|500px|thumb|Bioretention schematic, with circles highlighting ZVI addition and phosphorus removal <ref>Lechner L. Phosphorus Removal From Stormwater Using Zero-Valent Iron. 2016. Applied Science Masters Thesis.</ref>.]]
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[[File:Screenshot 2025-08-13 113919.png|500px|thumb|[[Bioretention]] schematic, with circles highlighting ZVI addition and phosphorus removal <ref>Lechner L. Phosphorus Removal From Stormwater Using Zero-Valent Iron. 2016. Applied Science Masters Thesis.</ref>.]]
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===Benefits===
 
===Benefits===
 
A study was done that compared the phosphorus reduction capabilities of ZVI, [[biochar]], biochar-supported ZVI (ZVI/BC), and biochar-supported nZVI (nZVI/BC). <ref name=Rossetti/> It was found that nZVI/BC had the highest phosphorus reduction. Using biochar-supported ZVI or nZVI improves the dispersion and stability of the iron filings. Biochar is fine-grained and highly porous, providing a large surface area to support nZVI.
 
A study was done that compared the phosphorus reduction capabilities of ZVI, [[biochar]], biochar-supported ZVI (ZVI/BC), and biochar-supported nZVI (nZVI/BC). <ref name=Rossetti/> It was found that nZVI/BC had the highest phosphorus reduction. Using biochar-supported ZVI or nZVI improves the dispersion and stability of the iron filings. Biochar is fine-grained and highly porous, providing a large surface area to support nZVI.

Revision as of 15:43, 13 August 2025

ZVI

What is it?[edit]

Iron filings or zero-valent iron (ZVI) is the elemental form of iron with a zero charge carried by each atom – a result of the outer valence level being filled. ZVI is able to remove dissolved phosphorus (phosphate) from solution through precipitation. [1] Zero-valent iron nanoparticles (nZVI) are also used for phosphorus removal.

How is it being used?[edit]

No projects that use ZVI were found in Ontario.

Bioretention schematic, with circles highlighting ZVI addition and phosphorus removal [2].

Benefits[edit]

A study was done that compared the phosphorus reduction capabilities of ZVI, biochar, biochar-supported ZVI (ZVI/BC), and biochar-supported nZVI (nZVI/BC). [1] It was found that nZVI/BC had the highest phosphorus reduction. Using biochar-supported ZVI or nZVI improves the dispersion and stability of the iron filings. Biochar is fine-grained and highly porous, providing a large surface area to support nZVI. Another paper reports that ZVI can remove up to 98% of influent phosphorus at low input concentrations, and at high concentrations is shown to remove up to 36% of incoming phosphorus. The phosphorus retained in the soil is mostly iron-bound, which will not be easily leached out of the system because it is very stable.[3]

Back to additives.

  1. 1.0 1.1 Rossetti M. Evaluation of phosphorous removals by biochar supported nano-scale zero-valent iron. 2017. Chemical Engineering Undergraduate Honors Thesis.
  2. Lechner L. Phosphorus Removal From Stormwater Using Zero-Valent Iron. 2016. Applied Science Masters Thesis.
  3. Lechner L. Phosphorus Removal From Stormwater Using Zero-Valent Iron. 2016. Applied Science Masters Thesis.