A magnetic Fe3O4@Fe-Ti composite nano adsorbent was aggregated to micrometer size for high efficiency fluoride removal and effective separation of the adsorbent from the water after defluoridation. The adsorption and separation performances of the micrometer-sized adsorbent were investigated. The granular adsorbent at an aggregated size of approximately 10 mu m had little intragranule diffusion resistance. This granule adsorbent was easily separated from water using magnetic separation after defluoridation. The thermal treatment at the best temperature, 200 degrees C, increased the granular strength without causing the undesired effects of magnetization decrease and crystallinity increase. For the adsorbent granules with an average size of 11 um that were heated at 200 degrees C for 1.5 h, the fluoride adsorption was completely achieved within only 2 min in a novel defluoridation process with a fluidized bed, and over 99% of the adsorbent was intercepted by using a magnetic separation unit. After a simple ultrafiltration unit, no adsorbent residue was detected in the outlet water, guaranteeing the safety of the drinking water. Compared with a traditional fixed-bed process, the fluidized-bed process in this work has the advantages of high defluoridation rate, small apparatus size, high security, and suitability for household utilization.