Title: Leaching of heavy metals from wastewater sludge, using a thermostatted column

Authors: J. Vite, C. Carreno, M. Vite

Addresses: Instituto Nacional de Investigaciones Nucleares, Apartado Postal 18-1027, Col. Escandon, Mexico C.P. 11801, Mexico. ' Instituto Nacional de Investigaciones Nucleares, Apartado Postal 18-1027, Col. Escandon, Mexico C.P. 11801, Mexico. ' Universidad de Guadalajara, Guadalajara, Mexico

Abstract: We have previously patented a process for the extraction of toxic and valuable metals from foundry sands using a thermostatted column. In this paper, we describe a similar device for the removal of toxic metals from wastewater sludge. The wastes were finely ground and suspended in an aqueous pulp, and 10-40g of mineral acid or sodium hydroxide were added to reach a pH of 2, 5, 7 and 10, together with 4-10 g of a bisulphite and 0.3-1.5 g of sodium dodecyl sulfate. In some cases, this method can remove 100% of heavy metals from samples of various wastewater sludges. To study the removal efficiency of heavy metals, we used inductively coupled plasma atomic emission spectrometry (ICP-AES). The metallic alloys in the samples were studied by X-ray diffraction.

Keywords: atomic emission spectroscopy; heavy metals; leaching; thermostatted column; wastewater sludge; X-ray diffraction; wastewater treatment.

DOI: 10.1504/IJEP.1997.028168

International Journal of Environment and Pollution, 1997 Vol.8 No.1/2, pp.201 - 207

Published online: 15 Sep 2009 *

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