Ferric EDTA

Ferric EDTA

Names
Other names (ethylenedinitrilo)tetraacetatoferrate
Identifiers
CAS Number	15275-07-7
3D model (JSmol)	Interactive image
ChemSpider	26311
EC Number	241-171-3
PubChem CID	28283
InChI InChI=1S/C10H16N2O8.Fe/c13-7(14)3-11(4-8(15)16)1-2-12(5-9(17)18)6-10(19)20;/h1-6H2,(H,13,14)(H,15,16)(H,17,18)(H,19,20);/q;+3/p-3 Key: UOMQUZPKALKDCA-UHFFFAOYSA-K
SMILES C(CN(CC(=O)[O-])CC(=O)[O-])N(CC(=O)O)CC(=O)[O-].[Fe+3]
Properties
Chemical formula	C10H12FeN2O8
Molar mass	344.06 g·mol−1
Appearance	colorless
Hazards
GHS pictograms
GHS signal word	Warning
GHS hazard statements	H315, H319
GHS precautionary statements	P264, P280, P302+352, P305+351+338, P321, P332+313, P337+313, P362
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Ferric EDTA is the coordination complex formed from ferric ions and EDTA. In contact with aerated natural waters, iron mainly exists in the ferric form. EDTA is a common chelating agent with a high affinity for ferric ions.^[1] Near neutral pH, the principle complex is [Fe(EDTA)(H₂O)]⁻, although most sources ignore the aquo ligand. The [Fe(EDTA)(H₂O)]⁻ anion has been crystallized with many cations, e.g., the trihydrate Na[Fe(EDTA)(H₂O)]^.2H₂O.^[2] The salts are yellow-brown.

Uses

Together with pentetic acid (DTPA), EDTA is widely used for sequestering metal ions that otherwise decompose hydrogen peroxide, which is used to bleach pulp in paper making. Several million kilograms are produced for this purpose annually.^[3]

Iron chelate is commonly used for agricultural purposes to treat chlorosis, a condition in which leaves produce insufficient chlorophyll. In horticulture, iron chelate is often referred to as 'sequestered iron' and is used as a plant tonic, often mixed with other nutrients and plant foods (e.g. seaweed). It is recommended in ornamental horticulture for feeding ericaceous plants like Rhododendrons if they are growing in calcareous soils. The sequestered iron is available to the ericaceous plants, without adjusting the soil's pH, and thus lime-induced chlorosis is prevented.

Iron chelate has also been used as a bait in the chemical control of slugs, snails and slaters in agriculture in Australia and New Zealand. They have advantages over other more generally poisonous substances used as their toxicity is more specific to molluscs.^[4]

Ferric EDTA is also used to control some broadleaf weeds in lawns.

Related derivatives

Aside from ferric edta, iron complex of EDDHA is used to make the iron soluble in water and, for the purposes of agriculture, accessible to plants.

In iron chelation therapy, deferoxamine, has been used to treat excess iron stores, i.e. haemochromatosis.^[5]

References