An adsorption study of Al(III) ions onto chitosan

C Septhum, S Rattanaphani, J B Bremner, V Rattanaphani
Journal of Hazardous Materials 2007 September 5, 148 (1): 185-91
The adsorption of Al(III) from aqueous solutions onto chitosan was studied in a batch system. The isotherms and the kinetics of adsorption with respect to the initial Al(III) concentration and temperature were investigated. Langmuir and Freundlich adsorption models were applied to describe the experimental isotherms. Equilibrium data fitted very well to the Langmuir model in the entire concentration range (5-40 mg/L). The negative values of free energy (DeltaG degrees ) and enthalpy (DeltaH degrees ) for the adsorption of Al(III) onto chitosan indicated that the adsorption process is a spontaneous and exothermic one. Two simplified kinetic models, based on pseudo first-order and pseudo second-order equations, were tested to describe the adsorption mechanism. The pseudo second-order kinetic model resulted in an activation energy of 56.4 kJ/mol. It is suggested that the overall rate of Al(III) ion adsorption is likely to be controlled by the chemical process. The values of the enthalpy (DeltaH(#)) and entropy (DeltaS(#)) of activation were 53.7 kJ/mol and -164.4 J/molK, respectively. The free energy of activation (DeltaG(#)) at 30 degrees C was 103.5 kJ/mol.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"