PRECONCENTRATION AND SEPARATION OF FE (III), CO (II), NI (II) AND ZN (II) BY SOLID-PHASE EXTRACTION USING SILICA MODIFIED WITH N- PROPYLSALICYLALDIMINE

PRECONCENTRATION AND SEPARATION OF FE (III), CO (II),
NI (II) AND ZN (II) BY SOLID-PHASE EXTRACTION USING
SILICA MODIFIED WITH N- PROPYLSALICYLALDIMINE
MOHAMED A. HAMED
National Institute of Oceanography and Fisheries, Suez, Egypt.
Keywords: preconcentration, separation, modified silica, metals and water.
ABSTRACT
N- propylsalicylaldimine based on porous silica, as ion exchanger, was used for the
separation and preconcentration of Fe
3+
, Co
2+
, Ni
2+
and Zn
2+
from surface water samples
collected from eleven locations at Nile river, Mediterranean and Red seas as well as tap
water of Mansoura city.
The effects of pH value, time of stirring, concentration of eluting acids and some
common ionic species on the separation and preconcentration of the investigated metal ions
in synthetic aqueous solutions were studied. The results indicate that the optimum
conditions for separation are pH = 9.0-9.5 and time of stirring = 30 min. HCl is better
eluent for the investigated metal ions than HNO3 except for Fe
3+
. Citrate and EDTA gave
severe interference on the recovery of the metal ions therefore the water samples were
previously oxidized to digest organic matter prior to the application process.