A new method for preparation of silica potassium cobalt hexacyanoferrate composite ion exchanger from silica sol

A new method for the preparation of porous silica*potassium cobalt hexacyanoferrate (SiO2 x KCoFC) composite from silica sol is described. Silica sol was first gelled with K4Fe(CN)6 solution. Then the resulting hydrogel, SiO2 x K4Fe(CN)6 was reacted with Co(NO3)2 solution in acetone to give the composite SiO2 x KCoFC hydrogel. The empirical formula of KCoFC in the composite was found to be K1x69Co 0.93Fe(CN)6. The removal efficiency of the composite for Cs was judged by measuring its distribution coefficient, Kd in 1M HCl solution containing 10 ppm Cs. The Kd of Cs was found to be 5.73 x 105 ml/g-composite. (author)