尖晶石型LiMn_2O_4的水热合成及其锂吸附性能  

Hydrothermal Synthesis and Lithium Adsorption Properties of LiMn_2O_4 Spinel

作　　者：孙淑英[1] 张钦辉[1] 于建国[1] 

机构地区：[1]华东理工大学化学工程联合国家重点实验室,上海200237

出　　处：《过程工程学报》2010年第1期185-189,共5页The Chinese Journal of Process Engineering

基　　金：国家自然科学基金资助项目(编号:20906022);上海市科委纳米专项基金资助项目(编号:0852nm021)

摘　　要：以Mn(NO3)2,LiOH和H2O2为原料,通过控制水热反应条件直接合成了尖晶石型LiMn2O4纳米线,经酸浸脱锂后得到对Li+具有特殊选择性吸附的离子筛.用XRD,HRTEM,SAED和共存金属离子的分配系数等手段对产物的晶相结构及吸附性能进行了研究.结果表明,水热反应条件对前驱体结构有较大影响,前驱体LiMn2O4和离子筛MnO2均为一维纳米线,离子筛对不同金属离子的选择性吸附顺序为Li+>>Ca2+>Mg2+>Na+>K+,说明离子筛具有较高的Li+选择性.Li+的分配系数为16770.63mL/g,是高温焙烧样品(7917.49mL/g)的2.12倍,表明一维纳米MnO2离子筛对Li+的选择性吸附性能有显著提高.Spinel-type ternary LiMn2O4 nanowires were synthesized via direct hydrothermal synthesis with Mn（NO3）2, LiOH and H2O2. The final low-dimensional MnO2 nanorod ion-sieve with selective adsorption property to lithium ion was prepared and further modified by acid treatment to completely extract lithium ions from the Li-Mn-O lattice. The effects of hydrothermal reaction conditions on the nanostructure, chemical stability and ion-exchange property of the LiMn2O4 precursor and MnO2 ion-sieve were systematically examined via XRD, HRTEM, SAED and lithium ion selective adsorption measurement. The results show that hydrothermal reaction conditions had the considerable effect on the structure of samples. The equilibrium distribution coefficient （Kd） of these metal ions was in the order of Li^＋〉Ca^2＋〉Mg^2＋〉Na^＋〉K^＋, indicating high selectivity for Li^＋, but much less for Na^＋, K^＋, Ca^2＋, and Mg^2＋. The distribution coefficient for Li^＋ was 16 770.63 mL/g, increased about 2.12 times compared with the bulky MnO2 ion-sieves （7 917.49 mL/g）, indicating remarkable improvement of the ion-sieve selectivity by the well-maintained nanowire structure.

关 键 词：水热合成 离子筛 LIMN2O4 吸附 锂 

分 类 号：TQ028.15[化学工程] TQ424.2