Removal of Ni2+ ions from aqueous solutions by using ion exchange resins

Ni2+ ions were removed from aq. solns. (vol. 100 mL, concn. about 30 g/L) by using a cation-exchange and chelating ion-exchange resins, each with mass of 40 g. The solns. were introduced into ion exchange resins-packed columns by (i) dropping with a speed of 2 mL/min or by (ii) pouring the total vol. of tested soln. The content of Ni2+ ions in eluates were detd. at 10 min intervals. Use of the cation exchanger and (ii) method of introducing solns. into the column was the most effective and resulted in a decrease of the Ni content to only about 6 g/L after 50 min of the process. More than double values of the final content of Ni2+ ions were obtained for the same cation exchanger and method (I) as well as for all types of chelating ion exchange resins irresp. of the method used for the soln. introduction.