A series of spinel Li-Mn-Ni composite oxides with theoretical chemical formula of LiNixMn2-xO4 （0〈_x〈_1.0） were synthesized by liquid phase method. Their structure and morphology were characterized by X-ray diffra...A series of spinel Li-Mn-Ni composite oxides with theoretical chemical formula of LiNixMn2-xO4 （0〈_x〈_1.0） were synthesized by liquid phase method. Their structure and morphology were characterized by X-ray diffractometry （XRD） and scanning electron microscopy （SEM）, respectively. The stability of these Ni-substituted spinel oxides prepared at different temperatures was investigated in acidic medium as well. The results show that Ni can be brought into the spinel framework completely to form well-crystallized product when x〈_0.5 and the optimized synthesis temperature is 800℃. LiNi0.4Mn1.6O4 prepared at 800℃ can maintain the spinel structure and morphology with Li extraction ratio of 30.37%, Mn extraction ratio of 8.78% and Ni extraction ratio of 1,82% during acid treatment. The incorporated Ni not only inhibits the dissolution of Mn, but also reduces the extraction of Li due to the lattice contraction展开更多
为了开发一种高效的锂吸附材料,从四川盆地页岩气废水(Shale Gas Wastewater,SGW)中回收锂资源,以应对电动汽车和储能行业对锂电池需求的急剧上升,研究通过固相反应合成H_(1.33)Mn_(1.67)O_(4)(HMO),并将壳聚糖(Chitosan,CTS)作为造粒剂...为了开发一种高效的锂吸附材料,从四川盆地页岩气废水(Shale Gas Wastewater,SGW)中回收锂资源,以应对电动汽车和储能行业对锂电池需求的急剧上升,研究通过固相反应合成H_(1.33)Mn_(1.67)O_(4)(HMO),并将壳聚糖(Chitosan,CTS)作为造粒剂,制备复合材料CTS/HMO。在SGW中,CTS/HMO对锂的吸附质量比达到7.83 mg/g,经5次吸附-解吸循环后吸附质量比仅下降1.25%,表现出较高的稳定性。动力学研究显示,准二级动力学模型更符合试验结果,表明吸附过程主要由化学吸附控制。等温吸附试验结果显示,CTS/HMO的吸附行为符合Langmuir模型,表明其为单层吸附。选择性试验进一步验证了CTS/HMO对锂的良好选择性,这归因于HMO尖晶石结构的离子筛效应。在固定床过滤试验中,流速为0.104 mL/min,床层总容积为7.7 cm^(3)时,该材料约在2950 min后达到饱和,显示出良好的吸附寿命;对不同流速下的固定床吸附进行Thomas模型拟合,结果显示较低流速下的吸附质量比较大。研究表明,CTS/HMO是一种具有良好前景的工业级锂吸附剂,适用于从SGW中提取锂资源,可为实现资源的可持续利用和环境保护提供新技术。展开更多
基金Project(2008BAB35B04) supported by the National Key Technology R&D Program of ChinaProject(CX2010B111) supported by the Innovation Program of Doctoral Research of Hunan Province, ChinaProject(2010QZZD003) supported by Advanced Research Program of Central South University, China
文摘A series of spinel Li-Mn-Ni composite oxides with theoretical chemical formula of LiNixMn2-xO4 （0〈_x〈_1.0） were synthesized by liquid phase method. Their structure and morphology were characterized by X-ray diffractometry （XRD） and scanning electron microscopy （SEM）, respectively. The stability of these Ni-substituted spinel oxides prepared at different temperatures was investigated in acidic medium as well. The results show that Ni can be brought into the spinel framework completely to form well-crystallized product when x〈_0.5 and the optimized synthesis temperature is 800℃. LiNi0.4Mn1.6O4 prepared at 800℃ can maintain the spinel structure and morphology with Li extraction ratio of 30.37%, Mn extraction ratio of 8.78% and Ni extraction ratio of 1,82% during acid treatment. The incorporated Ni not only inhibits the dissolution of Mn, but also reduces the extraction of Li due to the lattice contraction
