含金属离子赖氨酸水溶液的萃取分离

采用二(2-乙基己基)磷酸(P204)作萃取剂,航空煤油作稀释剂,对含有钙、镁、钠、钾等金属离子的赖氨酸水溶液进行萃取,以蒸馏水作为反萃取剂对有机相进行反萃取分离实验.结果表明,原料液初始pH值在4～5、P204与煤油体积比为3:2、有机相与水相比为2:1、反应萃取时间大于30min、搅拌转速约200rpm时,能够取得较好的萃取效果.以初始pH值≥3.5的蒸馏水为反萃取剂,蒸馏水与有机相体积比4:1,在150rpm的转速下搅拌20min能够较为完全地分离出赖氨酸,然后在其它条件相同的情况下,用初始pH＜1的蒸馏水对有机相再次反萃取可分离出金属离子,从而实现萃取剂的重复利用.     

P507与N53在煤油体系中对酚类物质萃取效率的比较研究

选用P507(0-(2-乙基已基)-2-乙基已基磷酸酯)和N503(N,N二-(1-甲基庚基)乙酰胺)2种有机萃取剂对酚的质量浓度为4 500 mg/L的废水进行处理.在煤油体系中,考察了油水体积比、pH值、萃取体系相比、萃取温度、萃取时间等因素对P507和N503萃取剂效果的影响.试验结果表明,在pH值为3～3.5,...     

1,4-双(辛烷基)哌嗪萃取体系萃取模拟电镀废水中的Co2+

将1,4-双(辛烷基)哌嗪、白油和乙酸异辛酯配制成萃取体系。利用该萃取体系萃取模拟电镀废水中的Co~(2+)。最佳萃取方案为:m(模拟电镀废水)∶m(萃取体系)=1∶1,m[1,4-双(辛烷基)哌嗪]∶m(白油)∶m(乙酸异辛酯)=1.00∶3.00∶0.50,萃取时间10 min,萃取pH值6.0。1,4-双(辛烷基)哌嗪萃取体系对Co~(2+)的饱和萃取量为221.2 mg/L。当pH值为5.5～6.5时,Co~(2+)的萃取率大于75.0%。另外,采用1,4-双(辛烷基)哌嗪萃取体系时,Co~(2+)的质量浓度范围较为宽泛。     

石家庄圣泰新型锂电池电解液添加剂技改扩能项目

<正>该项目位于河北省石家庄市圣泰化工有限公司厂区内,由石家庄圣泰化工有限公司投资建设,利用现有车间生产线改建220吨锂电池电解液添加剂(20吨甘油三腈、150吨磷酸酯系列产品、50吨4,4'-联-1,3-二氧戊环-2,2'-二酮),新建生产车间两座,扩建2800吨锂电池电解液添加剂生产线(400吨甲烷二磺酸亚甲环酯、400吨硫酸乙烯酯、2000吨2-羟基-4-甲硫基丁酸异丙酯),新建锂电池电解液添加剂干燥包装车间一座。     

溶剂萃取法处理硝基苯废水的操作条件优化

硝基苯在自然界中难以被生物降解,对生态和环境造成了严重的危害。采用萃取法处理硝基苯废水既可降低废水的危害,又可实现部分硝基苯回收。以环己烷和脂肪酸甲酯为萃取剂,考察了萃取时间、温度、pH值、相比[V(萃取剂)∶V(废水)]对硝基苯去除率的影响。结果表明:环己烷作为萃取剂时,硝基苯去除率要优于脂肪酸甲酯,在萃取时间20 min、温度35℃、相比1∶1、pH=6.4时,硝基苯去除率为97%。在此条件下进行三级错流萃取后,硝基苯浓度降至1.77 mg/L。同时,考察了环己烷的循环使用次数对萃取效率的影响。结果表明:环己烷循环使用30次后,萃取效率依然达到92.11%,说明环己烷再生后可以循环利用。     

PC-88A萃取镍离子的工艺条件探究与优化

研究了酸性萃取剂2-乙基己基磷酸单2-乙基己基酯(PC-88A)萃取镍离子的萃取条件,反萃相硫酸含量对反萃效率的影响,并进行了优化。结果表明,优化萃取条件为:萃取反应温度40℃,萃取剂的体积分数80%,原料液初始pH为6.5,萃取剂皂化率为10%,此时PC-88A对Ni(II)的萃取率高达98.0%。在此优化条件下获得的负载有机相,采用0.8 mol/L的硫酸进行反萃,反萃率达到93.6%。     

氯仿萃取回收己内酰胺的研究

以萃取回收甲苯法生产己内酰胺废液中的己内酰胺为目的,选择氯仿作萃取剂,进行了萃取回收己内酰胺的研究。考察了原料液的pH、萃取温度、萃取时间等因素对氯仿萃取己内酰胺过程的影响。结果表明,在酸性条件下该萃取过程分配比随pH的升高而增大,当pH=7时分配比最大;萃取过程为快速过程,20 min即可达到萃取平衡;水相中硫酸铵和1-磺酸基环己烷羧酸对萃取过程有盐析效应,使分配比增大;萃取过程受温度影响不大,焓变值ΔH=2.86 kJ/mol。实验确定了pH=7时己内酰胺在有机相与水相中的分配平衡关系,当有机相和水相体积比为1时,三级错流萃取的萃取率可达到98%以上。同时,进行了工业废水的萃取验证实验,结果表明,氯仿对废水中己内酰胺的萃取效果良好。     

溶剂萃取法回收间氨基苯基-β-羟乙基砜

染料中间体废水所含有机物品种多、毒性大、可生化性差、环境污染严重。本文应用溶剂萃取法回收了废水中的染料中间体间氨基苯基-β-羟乙基砜。研究了萃取剂种类、溶液、pH值、稀释剂含量对萃取分配系数的影响,同时研究了萃取剂的选择性和抗疲劳性。实验结果表明,利用甲基异丁基酮做为萃取剂,盐酸做为反萃剂,相比为2:1,经两级错流萃取,可以回收91％的氨基油,且萃取剂的选择性和抗疲劳性较好。实验证明溶剂萃取法用于回收氨基油是十分可行的。     

加盐萃取精馏分离苯-环己烷

测定不同萃取剂和盐对苯-环己烷共沸物相对挥发度的影响,研究不同质量分数的盐和萃取剂与原料液体积比对苯-环己烷体系相对挥发度的影响以及萃取剂加入速率和回流比对加盐萃取精馏的影响,按实验确定的最佳工艺条件进行重复实验。结果表明:采用N,N-二甲基甲酰胺(DMF)作为萃取剂,加入质量分数为15%的KAc,萃取剂与原料液体积比为0.75,萃取剂加入速率为6 mL/min,回流比为3,可得到纯度大于98%的环己烷。与常规萃取精馏相比,加盐萃取精馏所需萃取剂与原料液体积比小,所得环己烷的纯度较高。塔底釜液经减压精馏,可得质量分数大于99.5%的苯和苯质量分数小于0.15%的加盐萃取剂。     

混合醇萃取剂从浓缩盐湖卤水中萃取提硼的实验研究

以2-乙基-1,3-己二醇和异丁醇按照一定体积比组成混合萃取剂、航空煤油为稀释剂,萃取某硫酸盐型盐湖浓缩卤水中的硼。对萃取剂浓度、浓缩卤水pH、萃取相比、萃取温度、萃取时间、饱和萃取容量和反萃剂浓度、反萃相比等进行了实验研究。结果表明:2-乙基-1,3-己二醇、异丁醇和航空煤油体积比为1∶2∶3,卤水pH为3,萃取相比为1∶1,温度为20℃,萃取时间为5 min;将得到的富硼有机相用0.25 mol/L氢氧化钠溶液进行反萃,反萃相比为1∶2、温度为30℃、反萃取时间为15 min。经三级萃取及反萃,卤水中硼质量浓度降为0.8 mg/L,硼萃取率为99.99%,反萃率为99.78%,硼回收率为99.77%,萃取效果好。     

废旧锂离子电池制备锂离子筛及其应用研究进展

锂离子电池报废量爆发式增长,预计到2023年,废旧锂离子电池回收利用将是一个超过300亿元产值的新兴市场,其中,锂资源占可回收金属价值的一半。为探索锂资源高效回收技术,基于现阶段研究热点,讨论了以废旧锰酸锂电池正极材料、废旧三元锂电池正极材料、废旧锰系锂离子电池负极材料为原料制备锂离子筛的方法;探讨了废旧锂离子电池中各类杂质成分对锂离子筛性能的影响;阐述了锰系锂离子筛技术在废旧锂离子电池的锂回收、盐湖卤水提锂和化工制药废水提锂等领域的应用。通过分析得出,锂离子筛的应用能够增加锂盐回收率与回收纯度,降低技术成本,应用前景广阔。     

从商业化角度看锂-空气电池的发展

锂-空气电池的完全商业化,一直是该研究领域的目标。但实现该目标,必须考虑到各方面的问题,任何小的影响因素都应该尽量考虑在内。负极需要保护其不受水分、二氧化碳、电解液中反应中间物等物质的侵蚀,并抑制枝晶的产生。正极中高效的电极反应催化剂及能容纳放电产物的高比表面积结构是维持电池稳定循环的基本要求。合理的添加剂对电解液性能的提高也非常有必要。电池整体需考虑各种外部因素,如电池构造、尺寸放大等。目前有关锂?空气电池的研究已经取得了很多进展,但仍然缺少决定性突破。以商业化为最终目的,本综述从锂?氧气电池各组成部分切入,对近几年的研究进展进行总结,着重于电池体系整体的研究报道,对未来锂?空气电池的发展进行了展望。     

锂离子电池电解液负极成膜添加剂的研究进展

解决锂离子电池电极材料和电解液相容性的关键是形成稳定且Li⁺可导的固态电解质界面膜(SEI膜),因此,对优质负极成膜添加剂的研究成为锂离子电池研发中的一个热点。本文综述了锂离子电池电解液成膜添加剂的作用原理,具体介绍了各类负极成膜添加剂的研究现状,从成膜反应机理和理论计算方面详述了近几年来负极成膜添加剂的研究进展。分析了所存在的问题主要是如何快速地挑选出更适宜、更高效的成膜添加剂,并指出了成膜添加剂未来的发展趋势为:①研究各添加剂与电解液的反应机理,着重开发对锂离子电池副反应小的负极成膜添加剂;②通过选择两种或两种以上的添加剂的协同作用,以弥补一种添加剂的不足;③提高无机成膜添加剂在电解液中的溶解度。     

基于LiPF6的锂离子电池电解液的发展现状

近年来随着社会的发展和科技的进步,锂离子电池已成为重要的主流动力电池之一。分别从溶剂和添加剂2个方面综述了基于LiPF6的锂离子电池电解液的发展现状,详细介绍了适用于锂离子电池电解液的溶剂和添加剂,应用于锂离子电池电解液的常用有机溶剂有碳酸酯类、醚类和羧酸酯类有机溶剂,添加剂以其作用目的区分,可分为SEI成膜添加剂、导电添加剂、稳定添加剂、控制水分和游离酸添加剂、抗过充添加剂、阻燃添加剂及浸润性添加剂等;展望了锂离子电池电解液的研究方向。     

Influence of electrolyte additives on safety and cycle life of rechargeable lithium cells

The influence of electrolyte additives on the safety and cycle life of 4V-class lithium cells is examined. The electrolyte solution employed was 1 M LiClO₄-propylene carbonate, the most widely used electrolyte in lithium battery research. The additives studied were ten organic aromatic compounds including biphenyl, cyclohexylbenzene and hydrogenated diphenyleneoxide. For safety, focus was given to the overcharging tolerance of the lithium cells. Biphenyl is well-known as an overcharge protection additive. The purpose of this work was to find additives with a higher oxidation potential and longer charge–discharge cycle life than biphenyl. The oxidation potentials and currents of the additives were measured to determine whether or not these compounds work as overcharge protection additives. Charge–discharge cycling efficiencies were examined for lithium metal anodes. The results showed that cyclohexylbenzene and hydrogenated diphenyleneoxide have a higher oxidation potential and a higher lithium cycling efficiency than biphenyl.     

锂离子电池高压电解液研究进展

传统碳酸酯类电解液在高压(>4.3 V, vs. Li/Li+)下易发生氧化分解反应,导致锂离子电池不可逆容量增加、循环性能下降. 为解决这一问题,需从理论和实验两方面对电解液溶剂、锂盐、添加剂及其基本组成等进行针对性设计. 耐高压溶剂是提升电解液稳定性的关键因素之一,既经济又有效,添加高浓锂盐是近年来研究较多的可提升电解液电化学窗口和循环稳定性的新策略. 本工作从耐高压溶剂、高压添加剂和高浓锂盐三方面综述了近几年锂离子电池高压电解液的研究进展.     

A green approach for cohesive recycling and regeneration of electrode active materials from spent lithium-ion batteries

The implementation of the green energy transition by reducing reliance on fossil fuels has fueled the burgeoning demand for lithium-ion batteries in grid-level energy storage systems and electric vehicles. The growth of portable electronic devices has also contributed to this exponential demand, creating both logistical and environmental challenges in the supply of raw materials such as lithium and the management of end-of-life batteries. Current recycling methods for spent batteries are both energy-intensive and inefficient. To address these issues, a green approach using organic acid mixtures has been proposed to reclaim lithium from spent cathodes and recover and purify graphite from spent anodes, while also regenerating its structure. The effectiveness of this method is demonstrated through the use of organic acid mixtures to leach and reclaim lithium from NCM 622 batteries. On the anode side, a curing–leaching strategy using organic acids is employed to purify spent graphite, which is subsequently calcined to enhance its interlayer structure conducive to better intercalation of Li⁺ and improve electrochemical performance. Additionally, recovered graphite is tailored with carbon using water bath carbonization to repair structural defects caused by lithium intercalation and improve electrochemical performance while augmenting the regenerated graphite's quality, equipping it to be reused in batteries or upcycled applications.     

A study of the delay effect in SOCl2 batteries

Electrical and microstructural properties of the passive layers formed on lithium in SOCl₂ containing different additives (PVC, inorganic salts, cathode additives) were studied. LiCl crystals were found to be cubic, octahedral or needle-like. Typical passive layer thicknesses were 1–20 µm. The electrical properties of the passive layer were explained by referring to the space charge model of SEI conduction. It was pointed out that impedance spectroscopy may be selectively used as a non-destructive method for estimation of the galvanostatic behaviour of lithium batteries. The best results, as regards the elimination of the delay effect, were obtained with a combination of organic and inorganic electrolyte additives.     

酚油共萃协同解毒技术及其在煤化工高浓废水中的应用

煤化工高浓废水因成分复杂、污染物浓度高、毒性大、可生化性低等特点受到环保行业广泛关注,废水中含有高浓度的氨氮、酚类和油类物质及杂环化合物和多环芳烃等高毒性污染物,高效脱酚和深度解毒是该类废水处理的两大瓶颈。本工作从过程污染控制角度提出了酚油共萃协同解毒技术,配合研发的酚油联合脱除专用萃取剂IPE-PO,有针对性地处理云南某企业的煤化工高浓废水。用GC-MS检测了处理前后废水中的有机物种类,并与工业应用广泛的甲基异丁基酮萃取剂(MIBK)萃取体系进行对比。预处理后废水中的化学需氧量(COD)、总酚、氨氮(NH4+?N)、有机物的吸光度(UV254)平均脱除率分别为77.69%, 90.45%, 97.10%和82.19%,去除了大部分有毒污染物,废水的可生化性显著提高。处理后废水中的有机物种类从原水中的101种减至74种,展现了该技术在处理有毒物质方面的优势。经生化和深度处理,废水COD从31000~37000 mg/L降至100 mg/L以下,UV254从197 cm?1降至0.5 cm?1,可直接排入污水厂,运行成本不超过10元/t。IPE-PO萃取剂酚油协同共萃解毒技术在煤化工废水处理上是一种可行且高效的预处理方法。     

Characteristics of electrochemically synthesized polymer electrodes in lithium cells—II. Polythiophene

The characteristics of electrochemically synthesized polythiophene electrodes have been examined in view of their application in rechargeable lithium, organic electrolyte batteries. The kinetics of the electrochemical doping process of polythiophene in LiClO₄-propylene carbonate electrolyte are quite fast, especially for polymers grown from the 2,2′-dithiophene dimer. The polythiophene electrodes behave very satisfactorily in terms of charge-discharge efficiency and cyclability. However, also this type of electrodes seems to be affected by the self-discharge processes commonly experienced by semiconducting polymers in lithium, organic electrolyte batteries.