Abstract
Ion-exchange reaction of various protonated layer compounds with Bi3+ ion was carried out in order to investigate ion-exchange property of protonated layer compounds for a high valence cation. 14 kinds of protonated layer compounds were used such as HBiNb2O7·1.10H2O (HB), HNb3O8·0.97H2O (HN), H0.7Ti1.825O4·0.93H2O (HT), HLaNb2O7·0.17H2O (HLN), HCa2Nb3O10·1.2H2O (HCN), HFe0.5Nb1.5O5·0.63H2O (HFN), HTiNbO5·0.16H2O (HTN), H2Ti3O7·0.17H2O (HT237), H2Ti4O9·1.27H2O (HT249), H2K2Nb6O17·2.0H2O (HKN), HNbWO6·1.50H2O (HNW), H1.8 [Bi0.2Ca0.8NaNb3O10]·1.55H2O (HBCNN), H2W2O7·1.40H2O (HW) and α-Zr (HPO4) 2·H2O (α-ZrP). The ion-exchange reaction for each compound came to equilibrium longer than 36h. The highest uptake amount of Bi3+ ion was observed for HBCNN in which 87% of proton was exchanged. The uptake amount of Bi3+ ion decreased in order; HBCNN (87%)>HT (75%)>HT249 (72%)>HT237 (61%)>HW (60%)>HNW (48%)>HCN (33%)>HTN (27%)>HKN (21%)>HN (18%)>HLN (12%)>α-ZrP (9%) =HFN (9%)>HB (0%). This tendency of the uptake amount of Bi3+ ion was discussed by the charge density of protonated layer compounds.