Adsorption of Nickel Ion by Zeolite-Attapulgite Composite Nano-Size Adsorbent

The removal of Ni(II) from aqueous solution by batch adsorption technique using a zeolite-attapulgite composite nano-size adsorbent was investigated. After elementary characterization of this adsorbent, the influence of adsorbent concentration, initial Ni(II) concentration, pH, contact time and temperature on the selectivity and sensitivity of the removal process were investigated. Results showed that this absorbent was indeed nanoporous. Increase in adsorbent dosage led to increase in Ni(II) adsorption due to increased number of adsorption sites. Langmuir model fitted the experimental data better than Freundlich model. Adsorption process was found to be highly pH dependent. The optimum pH range for adsorption of Ni(II) was found to be >10. Adsorption equilibrium attained within 2 h time. The sorption of Ni(II) increased with rise of temperature.