三维有序大孔LiAlMnO_4的合成及其Li^+脱嵌行为(英文)

Three-Dimensionally Ordered Macroporous LiAlMnO_4:Preparation and Li^+ Extraction/Insertion Behavior

In the past half century,several methods like solvent extraction[1],precipitation[2]and ion exchange[3,4]have been extensively studied for lithium recovery from seawater and salt lake brine.

The Al-incorporated three-dimensionally ordered macroporous lithium manganese oxide LiAlMnO4 was synthesized by polymethyl methacrylate colloidal crystal template filled with the LiNO3,Al（NO3）3·9H2O and Mn（Ac）2·4H2O mixed solution.The corresponding HAlMnO4 as a new lithium ion-sieve was obtained after the dilute hydrochloric acid treatment.The results show that the macroporous diameter and porous wall thickness are 240 nm and 52 nm or so,respectively,and the XRD patterns of samples belong to the pure spinel phase.The Li＋ extraction rate of LiAlMnO4 reaches above 97% in the 0.1 mol·L^-1 HCl solution,while the solution loss of aluminum and manganese only has 0.45% and 0.23%,respectively,owing to the substitution of aluminum for tervalence manganese.The Li ＋ maximum uptake capacity is equal to 45.5 mg·g-1,reaching 96.3% of the theoretical value of HAlMnO4.Meanwhile,the uptake speed of Li＋ is obviously speeded up,and there is a quite high selectivity for Li＋ in the solution containing K^＋,Na^＋,Ca^2＋ and Mg^2＋.