Section 9
Chapter 8,097

Acid extraction and sequential fractionation of heavy metals in water treatment sludges

Mingot, J.I.; Obrador, A.; Alvarez, J.M.; Rico, M.I.

Environmental Technology 16(9): 869-876


ISSN/ISBN: 0959-3330
DOI: 10.1080/09593331608616325
Accession: 008096740

Download citation:  

A sequential extraction procedure for the partitioning of Cu, Cr, Ni, Pb and Zn has been applied to urban sewage sludges of different origin treatment and cation content. The sludges were further treated with HCl, HNO-3 and H-2SO-4 (pH = 1.5). By relating the amount of each cation extracted by acids with its fractionation, an equation was obtained enabling the amount extracted with acids to be estimated as a function thereof. Finally, the speciation of acid treatment residue compared to the initial one shows that although part of the cation content of all fractions including the residual one is mobilized, the reduction in the two most labile is so great that it can be the said that the sludge's polluting power is reduced to a greater degree of acid extraction than could be deduced from the overall extraction efficiency.

PDF emailed within 0-6 h: $19.90