Although magnetic separation based on paramagnetic beads has been successfully applied in many biotechnology fields (Jun et al., 2009), its potential application in purification of contamination water is attracting much attention (Rikers et al., 1998, Feng et al., 2000, Karapinar, 2003, Marius et al., 2005, Chin et al., 2006, Oka et al., 2008).