Thermodynamic study of adsorption of Cr(VI) on anion exchange fiber contaiming polyamine

The adsorption of Cr(VI) by using self-made anion exchange fiber contaiming polyamine functional group was studied. Within the observed temperature and concentration range, the adsorption quantity and adsorption rate were increased with temperature increasing. The results showed that the adsorption process was fast, and the adsorption process could be reached equilibrium in 20 minutes, the experimental data for the adsorption systems could be well described by the Boyd liquid film dispersal pattern. Equilibrium data for the adsorption of Cr(VI) from aqueous solutions by the fiber were obtained and correlated with the Langmuir-type and Freundlich-type isotherm equations, the adsorption is favourable type. The adsorption enthalpies, free energy changes and entropy changes of the fiber were also mensurated, the adsorption behavior was also reasonably interpreted. The results indicate that the adsorption is a decalescence process, and the chemical adsorption was the main adsorption process.