The modified fibers were first tested to remove some metallic cations from a model solution containing different cations. This model solution was a mixture of lead, zinc, nickel, and copper cations. The total concentration was 200 ppm Fig. 3 shows that after 10 passages, the retention efficiency of the modified fiber varied from 100 to 96% for lead, 99 to 96% for zinc, 99 to 85% for copper, and from 99 to 77% for nickel. Since the new modified fiber proved its capacity to remove different heavy metals, direct additional tests for the removal of metal ions from cooling tower water were performed.