Abstract:The reaction of synthesized Ca-bound, Fe-bound, and Al-bound organo-mineral complexes with Ca2+,Fe3+,and Al3+ ions in solution, respectively, was studied. The results showed that the Ca2+ or Al3+ in solution could not exchange the bound-Fe in complex, the Ca2+ or Fe3+in solution could exchange little bound-Al in complex, and Fe3+ or Al3+ in solution could exchange more bound-Ca in complex. However, the exchangeable capacity was related to pH in solution and type of clay minerals. Although the bound ions in complexes were hardly exchanged, the Ca2+,Fe3+,or Al3+ in solution could complex with organo-mineral complexes.