氯化亚锡作为还原剂在废旧锂离子电池有价金属浸出回收中的应用研究

The reductant is a critical factor in the hydrometallurgical recycling of valuable metals from spent lithium-ion batteries (LIBs). There is limited information regarding the use of SnCl₂ as a reductant with organic acid (maleic acid) for recovering valuable metals from spent LiCoO₂ material. In this study, the leaching efficiencies of Li and Co with 1 mol·L?1 of maleic acid and 0.3 mol·L?1 of SnCl₂ were found to be 98.67% and 97.5%, respectively, at 60°C and a reaction time of 40 min. We investigated the kinetics and thermodynamics of the leaching process in this study to better understand the mechanism of the leaching process. Based on a comparison with H₂O₂ with respect to leaching efficiency, the optimal leaching parameters, and the activation energy, we determined that it is feasible to replace H₂O₂ with SnCl₂ as a leaching reductant in the leaching process. In addition, when SnCl₂ is used in the acid-leaching process, Sn residue in the leachate may have a positive effect on the re-synthesis of nickel-rich cathode materials. Therefore, the results of this study provide a potential direction for the selection of reductants in the hydrometallurgical recovery of valuable metals from spent LIBs.     

碳包覆Ti3AlC2增强银基复合材料的制备与性能

Ti₃AlC₂-reinforced Ag-based composites, which are used as sliding current collectors, electrical contacts, and electrode materials, exhibit remarkable performances. However, the interfacial reactions between Ag and Ti₃AlC₂ significantly degrade the electrical and thermal properties of these composites. To diminish these interfacial reactions, we fabricated carbon-coated Ti₃AlC₂ particles (C@Ti₃AlC₂) as reinforcement and prepared Ag–10wt%C@Ti₃AlC₂ composites with carbon-layer thicknesses ranging from 50–200 nm. Compared with the uncoated Ag–Ti₃AlC₂ composite, Ag–C@Ti₃AlC₂ was found to have a better distribution of Ti₃AlC₂ particles. With increases in the carbon-layer thickness, the Vickers hardness value and relative density of Ag–C@Ti₃AlC₂ gradually decreases. With a carbon-layer thickness of 150 nm, we obtained the lowest resistivity of Ag–C@Ti₃AlC₂ of 29.4 135.5×10?9 Ω·m, which is half that of Ag–Ti₃AlC₂ (66.7 × 10?9 Ω·m). The thermal conductivity of Ag–C@Ti₃AlC₂ reached a maximum value of 135.5 W·m?1·K?1 with a 200-nm carbon coating (~1.8 times that of Ag–Ti₃AlC₂). These results indicate that the carbon-coating method is a feasible strategy for improving the performance of Ag–C@Ti₃AlC₂ composites.     

SiCf/Ti2AlNb复合材料的界面反应及热稳定性

界面反应层是影响SiC纤维(SiC_f)增强钛基复合材料力学性能的重要因素,本文研究了SiC_f/Ti₂AlNb复合材料在热等静压成型以及热暴露过程中的界面反应、界面元素分布规律和界面热稳定性.研究结果表明:SiC_f/Ti₂AlNb复合材料内部元素扩散形成的界面产物主要为TiC,在热暴露过程中出现了TiSi₂和NbSi₂相.SiC_f/Ti₂AlNb复合材料界面反应层的厚度长大符合Arrhenius定律,其界面反应层厚度长大速率随着热暴露温度的升高而增加.界面反应层长大激活能为24.27kJ/mol,界面层长大频率因子为2.80×10^-4 m/s^1/2.SiC_f/Ti₂AlNb复合材料界面在700℃及以下温度具备良好的热稳定性.     

色氨酸四苯基卟啉铁(Ⅲ)催化烯烃环氧化的研究

测定了色氨酸四苯基卟啉铁（Ⅲ）（简记为Fe〔Trp—TPP〕Cl）与锌粉、乙酸和咪唑组成的氧化模拟体系催化烯烃氧化的吸氧动力学曲线,研究了不同轴向配体对体系催化活性的影响。结果表明,该体系催化各类烯烃环氧化产物收率（Zn％）由高到低的顺序为:环已烯>1—癸烯>烯丙基丙酮>丙烯酸甲酯,用吡啶代替咪唑作轴向配体可明显提高体系的最高吸氧速度。     

钾在水煤气耐硫变换催化剂中的作用

应用微反、XRD和TPR技术,对水煤气耐硫变换Co-Mo-K—O/γ-Al_2O_3催化剂的性能进行了研究。结果表明,原料气中H_2S的浓度在100～500ppm的实验范围内,催化剂中钾的存在能抑制在操作温度大于250℃后产生的反硫化,显著地提高催化剂的活性。K_2O的含量约在10～12%时为佳。XRD观察到,在硫化态的催化剂上,钾以KHSO_3的形式存在。硫化态的催化剂在TPR谱上有两个被H_2还原峰,表明了低温峰(T_m在200～250℃)为硫化物的还原,高温峰(550℃)则对应于氧化物的还原。     

亚甲基烯酮与1－氧杂丁二烯环加成反应机理的研究

亚甲基烯酮与１－氧杂丁二烯环加成反应机理的研究盛颖宏，方德彩，傅孝愿（北京师范大学化学系，１００８７５．北京；第一作者２４岁，男，硕士生）关键词环加成；亚甲基烯酮；１－氧杂丁二烯；反应机理分类号Ｏ６２１．１３亚甲基烯酮与２，２－二甲基－５－亚甲基－１...     

镍—膦配合物催化偶联反应和多联苯的合成

利用镍－膦络合物Ｎｉ（Ｐｐｈ３）２Ｃｌ２，Ｎｉ（ＰＢｕ＾ｎ３）２Ｃｌ２，ＮｉＣｌ２·ｄｐｐｅ，ＮｉＣｌ２·ｄｐｐｐ以及无膦配体的二氯化镍作为催化剂，能有效地促进苯基格氏试剂和苯基卤化物的交叉偶联反应，方便地制取三、四、五联苯作为液晶及有机闪烁剂的原料。中着重对无膦酸体无水氯化镍的作用范围和及应用机理进行了讨论。     

合成啡赛立啶的新方法

报道了一条合成ＰＣＰ的新方法，与原工艺比较，新方法收率高、省原料、操作容易。     

聚苯乙烯负载手性化合物的合成

介绍了-种简单而有效地制备聚苯乙烯负载手性化合物的新方法．以无水三氯化铝、1，2-二氯乙烷为催化剂和溶剂，在室温下利用N-邻苯二甲酰-L-谷氨酰氯与聚苯乙烯发生傅-克酰化反应，合成了聚苯乙烯负载的手性化合物，并通过FT-IR和元素分析对产物进行了表征．