The adsorbent H8,Nb22,O59·8H2O was obtained through extracting Rb+from Rb8,Nb22,O59 in the 10 mol/L HNO3 solution,the K+exchange capacity of H8,Nb22,O59·8H2O was studied,and samples were characterized with XRD and SEM, respectively. The results indicate that the structure of H8,Nb22,O59·8H2O is similar with that of Rb8,Nb22,O59,and the saturated adsorption capacities of Na+and K+for H8,Nb22,O59·8H2O are close to the theoretical value of 2.55 mmol/g,suggesting that the adsorbent H8,Nb22,O59·8H2O has a higher affinity for Na+and K+. H8,Nb22,O59·8H2O shows markedly high selectivity for the adsorption of K+within the pH range from 2 to 8,but separation factor decreases with the increase of pH value,and re-used H8,Nb22,O59·8H2O still exhibits markedly high selectivity for the adsorption of K+.% 用浓度为10,mol/L HNO3对高温固相合成的 Rb8,Nb22,O59进行酸洗脱 Rb+,制得吸附剂 H8,Nb22,O59·8H2O,并对K+的交换性能进行研究,同时运用XRD和SEM进行表征.结果表明：H8,Nb22,O59·8H2O与Rb8,Nb22,O59具有相似的结构；H8,Nb22,O59·8H2O对于Na+和K+的饱和吸附量接近理论吸附量2.55,mmol/g,表明吸附剂对Na+和K+具有较高的亲和性；在pH为2~8的范围内,H8,Nb22,O59·8H2O对K+具有较高的分配系数,而分离因数随pH的升高而显著降低；H8,Nb22,O59·8H2O重复使用后对K+仍具有较高的吸附选择性.
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