Preparation of Ammonium Tungstophosphate-Calcium Alginate Composite Adsorbent and its Adsorption Properties of Rubidium

A spherical composite adsorbent AWP-CaALG was prepared by the calcium alginate(CaALG) and ammonium tungstophosphate(AWP). The composite adsorbent was characterized by XRD, FT-IR and TG-DTG-DTA, it proves that the crystal structure of AWP isn’t destroyed and the adsorption ability of the composite adsorbent can be retained up to 120°C. Effects of adsorbent dosage, adsorption time, pH, temperature, concentration of Rb and K were investigated. The results show that the adsorption capacity of composite adsorbent to rubidium is 20.64mg/g.The adsorption equilibrium is gained after 24h. When the concentration ratio of K to Rb is 16, the adsorption rate of Rb can still be up to 94.1% and the Rb/K separation coefficient is 86.