Chemical treatment of chelated metal finishing wastes.
Water Environ Res
; 84(12): 2086-9, 2012 Dec.
Article
en En
| MEDLINE
| ID: mdl-23342939
This study evaluated two chemical approaches for treatment of commingled cadmium-cyanide (Cd-CN) and zinc-nickel (Zn-Ni) wastewaters. The first approach, which involved application of sodium hypochlorite (NaOCl), focused on elimination of chelating substances. The second approach evaluated the use of sodium dimethyldithiocarbamate (DMDTC) to specifically target and precipitate regulated heavy metals. Results demonstrated that by maintaining a pH of 10.0 and an oxidation-reduction potential (ORP) value of +600 mV, NaOCl treatment was effective in eliminating all chelating substances. Cadmium, chromium, nickel, and zinc solution concentrations were reduced from 0.27, 4.44, 0.06, and 0.10 ppm to 0.16, 0.17, 0.03, and 0.06 ppm, respectively. Similarly, a 1% DMDTC solution reduced these same metal concentrations in commingled wastewater to 0.009, 1.142, 0.036, and 0.320 ppm. Increasing the DMDTC concentration to 2% improved the removal of all regulated heavy metals except zinc, the removal of which at high pH values is limited by its amphotericity.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Hipoclorito de Sodio
/
Quelantes
/
Purificación del Agua
/
Metales Pesados
/
Dimetilditiocarbamato
/
Aguas Residuales
/
Residuos Industriales
Idioma:
En
Revista:
Water Environ Res
Asunto de la revista:
SAUDE AMBIENTAL
/
TOXICOLOGIA
Año:
2012
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos