Investigation on cation uptake properties ofCaO:Al2O3:SiO2compounds synthesized by chemical route

Pollution of water with heavy metals as a result of industrial activities is a serious problem in the new century. Various methods such as ion exchange and adsorption with different material such as active carbon، zeolites، agricultural waste، industrial by-product and other natural or synthesized compounds have been used for the removal of heavy metals from waste waters. In this study، various compounds in CaO: Al2O3: SiO2system were obtained from chemical route and after calcination at 600-1000 ℃were used for uptake of Ni2+ cation from aqueous solution. From different synthesized compounds، calcined sample at 600℃ with chemical analysis CaO=40. 9%، Al2O3=37. 2% and SiO2=21. 9% wt. (C2AS-6 sample) were selected for removal of Ni2+ pollutant. Uptake experiments were performed with batch method at room temperature and at a solid: solution ratio of 0. 002g/mlwith Ni2+cation concentrations 30-70 mg/l at constant time 20 min to 24hr. It was found that the Langmuir and DKR models best fit with results of this research. Maximum adsorption capacity equal 21. 1 mg/g and mean energy of adsorption equal 11. 2 KJ/mol were obtained in this study. These results represent that monolayer coverage of Ni2+ on C2AS sample formed during contact of sample with solution and exchange cation mechanism responsible for proper removal of Ni2+ polluant from aqueous solution.