Iron chelates such as ethylenediamine-N,N'-bis(2-hydroxyphenylacetic)
acid (o,o-
EDDHA) and their analogues are the most efficient soil
fertilizers to treat
iron chlorosis in plants growing in calcareous soil. A new
chelating agent, HJB (N,N'-bis(2-hydroxy-5-methylphenyl)ethylendiamine-N,N'-diacetic acid) may be an alternative to o,o-
EDDHA since its synthesis yields a purer product, but its chemical behavior and efficiency as
chlorosis corrector should be evaluated. In this research, a known analogous
HBED (N,N'-bis(2-hydroxyphenyl)ethylendiamine-N,N'-diacetic acid) has also been considered. First, an ion-pair high performance liquid chromatography (HPLC) method has been tested for the HJB/Fe(3+) and
HBED/Fe(3+) determination. The ability of HJB and
HBED to maintain Fe in
solution has been compared with respect to o,o-
EDDHA. Theoretical modelization for
HBED and HJB in agronomic conditions has been done after the determination of the protonation and Ca(II), Mg(II), Fe(III), and Cu(II) stability constants for HJB. Also, batch interaction experiments with
soils and soil materials have been conducted. According to our results, HJB/Fe(3+) and
HBED/Fe(3+) present high stability, even when competing
cations (Cu(2+), Ca(2+)) are present, and have low reactivity with
soils and soil components. The
chelating agent HJB dissolves a higher amount of Fe than o,o-
EDDHA, and it seems as effective as o,o-
EDDHA in keeping Fe in
solution. These results indicate that these chelates may be very efficient products to correct Fe
chlorosis, and additional plant experiments should demonstrate plants' ability to assimilate Fe from HJB/Fe(3+) and
HBED/Fe(3+).