Pb(II) and Cd(II) biosorption on Chondracanthus chamissoi (a red alga)

• Published in: Journal of hazardous materials 2011-01, Vol.185 (2), p.922-929
• Main Authors: Yipmantin, Andrea, Maldonado, Holger J., Ly, Martha, Taulemesse, Jean Marie, Guibal, Eric
• Format: Article
• Language: English
• Subjects: Adsorption; Affinity; Applied sciences; Biological and medical sciences; Biomass; biosorbents; biosorption; Biotechnology; Cadmium; Cadmium - metabolism; Carrageenan; Chemical engineering; Chondracanthus chamissoi; Diffusion; Engineering Sciences; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Grinding; Hydrogen-Ion Concentration; Kinetics; Lead; Lead - metabolism; metal ions; Methods. Procedures. Technologies; Microscopy, Electron, Scanning; Optimization; Others; Particle Size; Pollution; Polysaccharides; Rhodophyta; Rhodophyta - metabolism; Solid-solid systems; Sorption; Sorption isotherms; Thermodynamics; Uptake kinetics; Uptakes; Various methods and equipments
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2010.09.108

Chondracanthus chamissoi is an efficient biosorbent for Pb(II) and Cd(II). The sorption efficiency increases with pH and reaches an optimum around pH 4. Maximum sorption capacity reaches 1.37 mmol Pb g −1 and 0.76 mmol Cd g −1. The biosorbent has a marked preference for Pb(II) over Cd(II), though insufficient for separating these metals by a simple sorption step. The uptake kinetics is controlled by the resistance to intraparticle diffusion with a limited impact of particle size, metal concentration and sorbent dosage. In the present case, grinding the biomass does not improve sorption capacity and uptake kinetics. The sorption of metal ions is probably due to their interaction with carrageenan (one of the main constituents of the biosorbent): sulfonic groups (on the sulfated polysaccharide) have a higher affinity for Pb(II) than for Cd(II) according to HSAB rules.