Chitosan metal ions, interaction with

Guibal, E. (2004). Metal ion interactions with chitosan—K review. Separ. Purif. Technol. 38 (1), 43-74. 

The adsorption capacity also depends on the temperature. In general, an increase in temperature decreases the saturation adsorption capacity of chitosan. The temperature had a dramatic effect on the adsorption metal ions on peanut husk. The adsorption capacity rose at the begirming with increase in temperature but thereafter it shows a decrease. The process is controlled by the adsorbate-adsorbent interactive forces. The results indicate that chemical adsorption becomes stronger in comparison to physical adsorption as the temperature increases [12]. Aksu et al. (1992) reported that the temperature seems not to influence the biosorption performances in the range of 20-35°C. The kinetic energy of the metal ions increased with increase in temperature and as a result of this the forces of attraction between the metal ions and the adsorbent gets weakened. Increase in... 

Because of its cationic characta-, chitosan interacts with negatively charged biological surfaces, such as skin and hair [200]. Otha- relevant characteristics of chitosan for cosmetic applications are its high molecular weight, water retention and film formation capacity as well as its heavy metal ion complexing abOity. 

Guibal, E. 2004. Interactions of metal ions with chitosan-based sorbents A review. Sep. Purif. Technol. 38 43-74. 

Chitosan (> 75% deacetylation, 800-2000 cps) was mixed with stock solutions of Cu(II), Fe(II), Cd(II) and Zn(II), prepared in 0.1 M HNO3, and of Ca(II) and Mn(II), in 0.1 MHCl. It was found that, in the chelation of most metal ions by chitosan, 1 1 binding of chitosan is more dominant than 2 1 cooperative binding, but vice versa for Zn(II) and Cd(II). The chelation of Cu(II) by chitosan showed much higher reactivity when compared to other divalent metal ions. Cu(II), Fe(II), Cd(II) andZn(II) showed strong reactivity and stability of their chelates. In contrast, the interactions between Ca(II) or Mn(II) and chitosan were almost negligible. These data confirm brilliantly previous data by Muzzarelli et al. [116]. 

In addition, chitosan has excellent properties for the adsorption of metal ions, principally due to the presence of amino groups (-NH2) in the potymer chain, which can interact with metal ions in solution hy ion exchange and complexation reactions (TVan et al., 2010). The cationic property of chitosan supplies the sites for electrostatic interactions, which are the responsible to bind this biopol3mier to certain anionic compounds (Lin and Pascall, 2014). 

Guibal, E., Touraud, E., and Roussy, J. 2005. Chitosan interactions with metal ions and dyes Dissolved-state vs. solid-state apphcation. World J. Microbiol. Biotechnol. 21 913-920. 

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