Effective Removal of Sr2+ Ions by K2SbPO6/Polyacrylonitrile Composite Microspheres

90Sr is one of the highly radioactive and hazardous nuclides in nuclear waste liquids. The high water solubility and mobility of 90Sr2+ ions make it difficult to effectively remove 90Sr from the complex aqueous environment. Herein, K2SbPO6, a phosphatoantimonate ion exchange material with an excellent removal ability for Sr2+ ions, has been organically granulated with polyacrylonitrile (PAN) by an automated method to form K2SbPO6/PAN composite microspheres. The K2SbPO6/PAN microspheres with radiation resistance exhibit a high maximum adsorption capacity (qmSr) of 131.15 mg g−1 for Sr2+ ions and retain the high removal rate (RSr) in a wide pH range (pH = 3–12). It is important that K2SbPO6/PAN microspheres could efficiently treat Sr2+ ions solutions in a dynamic adsorption manner even at 970 bed volumes (RSr > 81%). This work paves the way for the preparation of low-cost ion exchange materials with the advantages of regular shape and easy operation by a simple and fast method and the practical application of powdered ion exchange materials.