Original scientific paper
https://doi.org/10.5599/jese.2015.0055
Electrokinetic removal of heavy metals from soil
Puvvadi Venkata Sivapullaiah
; Department of Civil Engineering, Indian Institute of Science, Bangalore – 560 012, India
Bangalore Sriakantappa Nagendra Prakash
; Department of Civil Engineering, UVCE, Jnana Bharathi Campus, Bangalore University, Bangalore -560 087, India
Belagumba Nagahanumantharao Suma
; Department of Civil Engineering, UVCE, Jnana Bharathi Campus, Bangalore University, Bangalore -560 087, India
Abstract
Removal of heavy metal ions from soils by electrokinetic treatment has several advantages. The extent of removal, however, is both soil specific and ion specific. The conditions to be maintained have to be established based on laboratory studies. With a view to maximize the removal of metal ions the trends of removal of heavy metal ions such as iron, nickel and cadmium form a natural Indian kaolinitic red earth during different conditions maintained in the electrokinetic extraction process are studied. A laboratory electrokinetic extraction apparatus was assembled for this purpose. Attempts are also made to elucidate the mechanism of removal of the metal ions from soil. The composition of the flushing fluid, voltage and duration of extraction are varied. While dilute acetic acid has been used to neutralize the alkalinity that develops at the cathode, EDTA solution has been used to desorb heavy metals from clay surface. Generally the extent of removal was proportional to the osmotic flow. Nickel and Cadmium are more effectively removed than iron. The percentage removal of Ni is generally proportional to the osmotic flow but shows sensitivity to the pH of the system. There is an optimum voltage for removal of metal ions from soil. The removal of iron was negligible under different conditions studied.
Keywords
Electric; Clays; Metal ions; Removal; Sorption
Hrčak ID:
136655
URI
Publication date:
15.3.2015.
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