Facile deferration of commercial fertilizers containing iron chelates for their NMR analysis.
Ethylenediamine-N,N'-bis(o-hydroxyphenylacetic) acid (o,o-EDDHA) is widely used in commercial formulations as a Fe(3+) chelating agent to remedy iron shortage in calcareous and alkaline soils. Commercially available o,o-EDDHA-Fe(3+) formulations contain a mixture of EDDHA regioisomers (o,p-EDDHA and p,p-EDDHA), together with other, still uncharacterized, products. NMR spectroscopy can be applied to their study as long as iron is accurately removed prior to the observation. This paper shows that it is possible to obtain a deferrated solution of the organic ligands present in commercial fertilizers containing the EDDHA-Fe(3+) chelate by treating the chelate with ferrocyanide, thus forming Prussian Blue that can be easily removed by centrifugation. This iron removal process does not cause significant losses of the o,o-EDDHA ligand or its minor structural isomers.
Laghi
Luca
L
Department of Food Science, University of Bologna at Cesena, Cesena, Italy.
Alcañiz
Sara
S
Cerdán
Mar
M
Gomez-Gallego
Mar
M
Sierra
Miguel Angel
MA
Placucci
Giuseppe
G
Cremonini
Mauro Andrea
MA
D005029:Ethylenediamines / Q000737:chemistry*; D005308:Fertilizers / Q000032:analysis*; D007501:Iron / Q000737:chemistry; D007502:Iron Chelating Agents / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*
D005029:Ethylenediamines; D005308:Fertilizers; D007502:Iron Chelating Agents; C011813:ethylenediamine-N,N'-bis(2-hydroxyphenylacetic acid); D007501:Iron