PAN-H1.6Mn1.6O4 lithium ion-sieve membrane was prepared by blend of lithium ion sieve (H1.6Mn1.6O4) with hydrophilic polymer poly(acrylonitrile) (PAN). The effects of adding amount of lithium ion sieve for PAN-H1.6Mn1.6O4 membrane structure and Li+ adsorption-desorption properties were investigated by SEM, Li+ static adsorption, (NH4)2S2O8 elution and adsorption experiments in brine. The results showed that the adsorption capacity of PAN-H1.6Mn1.6O4 membrane (17.45 mg·g−1) achieved to 88.0% of H1.6Mn1.6O4 powder when the concentration of PAN was 10% (mass) and the amount of loading of H1.6Mn1.6O4 was 50% (mass). In addition, when (NH4)2S2O8 solution was used as eluent with the eluent concentration, liquid-solid ratio and time of 0.3 mol·L−1, 600:1 and 12 h, respectively, the amount of lithium ion elution was 17.23 mg·g−1 and the manganese loss of ratio was only 1.14%. The PAN-H1.6Mn1.6O4 membrane showed good selectivity for Li+ in Lop Nor brine containing other cations such as Na+, K+, Mg2+and Ca2+. After ten times adsorption-desorption cycles in brine, the adsorption capacity of lithium ion was lost only 6.0% (from 11.64 mg·g−1to 10.94 mg·g−1). Overall results demonstrated that using hydrophilic PAN carrier material had little effect on the adsorption capacity of H1.6Mn1.6O4 for lithium ion, and the mild eluent was favorable to chemical stability of lithium-ion sieve membrane.%采用亲水的PAN为成膜材料，制备了掺杂H1.6Mn1.6O4的PAN-H1.6Mn1.6O4锂离子筛膜。通过SEM、Li+静态吸附实验、(NH4)2S2O8对锂的洗脱实验和卤水中吸附实验，研究了锂离子筛的添加量对PAN-H1.6Mn1.6O4锂离子筛膜结构、Li+吸附-洗脱性能的影响。结果表明，PAN浓度为10%（质量），H1.6Mn1.6O4的添加量为50%（质量）时，PAN-H1.6Mn1.6O4离子筛膜的吸附量为17.45 mg·g−1，达到粉末状吸附量的88.0%。以(NH4)2S2O8为洗脱剂，当浓度为0.3 mol·L−1、液固比为600：1、时间为12 h时，锂洗脱量为17.23 mg·g−1，锰溶损率仅为1.14%。在含有Na+、K+、Mg2+和Ca2+的罗布泊老卤卤水中，锂离子筛膜对Li+有很高的选择性。在卤水中进行10次吸附与解吸循环，吸附量从11.64 mg·g−1下降到10.94 mg·g−1，吸附容量仅损失6.0%。总体结果表明亲水性载体对 H1.6Mn1.6O4吸附容量影响较小，温和的洗脱剂对锂离子筛膜的化学稳定性有利。
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