Mcma. Ferraz et Jcn. Lourenco, The influence of organic matter content of contaminated soils on the leaching rate of heavy metals, ENVIRON PR, 19(1), 2000, pp. 53-58
Leaching studies of contaminated soils were conducted to remove heavy metal
s, with the dim of recovering these species. Lead copper and zinc were extr
acted using a leaching solution of HCl (0.1 M) and NaCl (1.9 M). Time-depen
dent release was analyzed A Langmuir-type model fit well to the experimenta
l data, allowing the determination of the maximum concentration of lead cop
per and zinc that can be reached in the leaching solutions and the time req
uired to attain dfixed leached concentration of metal. The influence of nat
ural organic matter content of the soil on leaching time was evaluated. Nat
ural organic matter content influenced leaching time, due to metal complexa
tion dissolved organic matter transferred to the leaching solutions. Increa
sing of natural organic matter content of contaminated soils reduced leachi
ng time.