NEUTRALIZATION OF HEAVY METALS IN WATER AND SOILS BY IMMOBILIZATION INTO INSOLUBLE COMPLEXES, INABSORBABLE BY PLANTS

6th International Scientific Conference - SGEM2006, www.sgem.org, SGEM2006 Conference Proceedings/ ISBN: 954-918181-2, June 12-16, 2006, Vol. 1, 325-336 pp

ABSTRACT
/Full article available only in Bulgarian language/

We present a method for the neutralisation of heavy metals – Pb, Zn, Cd and Cr in contaminated water and soils by binding them into water-insoluble complexes, inabsorbable by plants, which was found to be effective under laboratory and green-house conditions.
By introducing multiblock copolyethers (MBPE) and low molecular weight organic chelates (LOC) in water, containing heavy metal ions, they interact stoichiometrically and precipitate, affording water of irrigation quality.
Treatment with MBPE and LOC (by single application with the irrigating water) of metal contaminated soils lead to stoichiometric binding of the toxic metals into water insoluble complexes, inabsorbable by plants. The heavy metal levels in plants were commeasurable with controls grown on clean soil.
In the concentrations studied, the chemical agents did not affect soil micro-organisms, they stimulated plant growth and preserved the fine granular soil structure and soil moisture.
The method could be useful for purification of industrial water from heavy metals, for soil remediation, as well as in emergency management of accidental spillage, or disasters, to limit heavy metal pollution.