Heavy metal extraction by a counter-flow moving bed reactor

Azza H. Ali, M. Abdelaziz, H. F. Elbakhshawangy, Sameh H. Othman

Nuclear Research Center, Atomic Energy Authority, Cairo, Egypt.
Nuclear Research Center, Atomic Energy Authority, Cairo, Egypt;.

DOI: 10.4236/ns.2012.412128                

Abstract

In the current study, the extraction of heavy metal ions (Zn²⁺, Cu²⁺ and Cd²⁺) is suggested to be achieved by a counter-flow moving bed reactor. The studies are made at high (1 × 10^-2 M) and low (1 × 10^-4 M) initial concentrations of the heavy metal ions. Theoretical and experimental studies are made on the extraction of the metal ions with impregnated Amberlite resins, prepared by sorption of an organic extractant into the resin. The study suggests structural, kinetic and hydrodynamic parameters that shall be investigated prior to the design of a moving bed reactor. The effect of these parameters on the adsorption extent is theoretically investigated through the proposed model. Analyses of the experimentally estimated external, internal and chemical rate parameters show that the process is controlled by chemical reaction in both concentrations as the chemical reaction rate parameter is significantly smaller than both the internal and the external diffusion rate parameters.

Keywords

Chemical Reactors; Diffusion; Mathematical Modeling; Hydrodynamic Parameters; Heavy Metals; Amberlite Resins

Conflicts of Interest

The authors declare no conflicts of interest.

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