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Published on: June 8, 2022
Metal biosorption equilibria in a ternary system
1Department of Chemical Engineering, McGill University, 3480 University Street, Montreal, Quebec, H3A 2A7 Canada.
Biotechnology and Bioengineering
|March 20, 1996
Summary
Ascophyllum nodosum seaweed effectively removes copper, cadmium, and zinc from water. The multicomponent Langmuir model showed nonideal metal uptake, limiting prediction accuracy for mixed solutions.
Area of Science:
- Environmental Science
- Water Treatment
- Materials Science
Background:
- Heavy metal contamination in aquatic environments poses significant risks.
- Biosorbents offer a sustainable approach for removing toxic metals from wastewater.
- Ascophyllum nodosum is a readily available seaweed biomass with potential biosorptive properties.
Purpose of the Study:
- To evaluate the equilibrium metal uptake capacity of Ascophyllum nodosum for copper, cadmium, and zinc.
- To investigate the sorption behavior of these metals in binary and ternary mixtures.
- To assess the applicability of the multicomponent Langmuir model for predicting ternary metal sorption.
Main Methods:
- Preparation of a biosorbent from Ascophyllum nodosum seaweed biomass.
- Batch equilibrium studies using aqueous solutions with copper, cadmium, and zinc ions.
- Graphical representation of ternary equilibrium data using triangular diagrams.
- Application and analysis of the multicomponent Langmuir model.
Main Results:
- Ascophyllum nodosum demonstrated metal uptake capabilities in binary and ternary systems.
- Triangular equilibrium diagrams effectively visualized ternary sorption data.
- The multicomponent Langmuir model indicated nonideal sorption characteristics for the metal mixtures.
- Apparent dissociation constants varied across different metal systems, hindering direct prediction from binary data.
Conclusions:
- Ascophyllum nodosum is a viable biosorbent for removing copper, cadmium, and zinc.
- The multicomponent Langmuir model's predictive power for ternary systems was limited due to nonideal interactions.
- Experimental data and binary subsystem analysis provided insights into ternary system behavior.
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