Assessment of interference in biosorption of a heavy metal
- McGill Univ., Montreal, Quebec (Canada). Dept. of Chemical Engineering
- Univ. Federal de Minas Gerais, Belo Horizonte (Brazil). Dept. of Metallurgical Engineering
Biosorption of heavy metals by various biological materials has been studied extensively in the last decade due to its potential particularly in wastewater treatment. The presence of a large number of metals in industrial metal-bearing solutions makes it necessary to investigate their effect on the final metal uptake by individual biosorbent materials. Nonliving biomass of Sargassum, a brown marine alga, is capable of binding more than 10% of its dry weight in toxic cadmium ions. Although ubiquitous iron interferes with Cd uptake, only approximately 4.5% of it is sequestered (biomass dry weight). Biosorption of both metals at pH 4.5 could be described by Langmuir-type isotherms with b, the affinity-related coefficient (Cd: b = 0.015; Fe: b = 0.027). The interference of Fe with Cd uptake, and vice versa, was assessed by deriving three-dimensional equilibrium two-metal sorption isotherm surfaces, smoothed and cut to reveal the inhibition effect of Fe on biosorption of Cd: at the equilibrium concentration Cf[Cd] = 1.5 mM, the presence of Fe at 1.5 mM equilibrium concentration suppressed the Cd uptake to only 76% of the original value. For 50% Cd uptake reduction, a very high equilibrium Fe presence of 4.5 mM was required. The Cd presence affected the uptake of Fe very strongly. To obtain equal values of uptake for each metal in the biosorbent, the ratio of equilibrium concentrations of 0.42 Cd to 1 Fe is necessary in the liquid phase.
- OSTI ID:
- 566330
- Journal Information:
- Biotechnology and Bioengineering, Vol. 54, Issue 4; Other Information: PBD: 20 May 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
Biosorption of cadmium by biomass of marine algae
Solution and particle effects on the biosorption of heavy metals by seaweed biomass