PMBP萃取分离偶氮胂Ⅲ光度法测定锌基稀土合金中镧和铈

锌基稀土合金是镀锌行业中一种热镀用新材料。稀土的含量直接影响镀层的质量和锌的消耗量。稀土测定常用发射光谱、质谱等大型仪器检测。化学法分析分离单个稀土元素比较困难 ,而且手续繁杂。本文在文献 [1,2 ]基础上 ,在 0 .5ｍｏｌ·Ｌ- 1盐酸、0 .5ｍｏｌ·Ｌ- 1硫氰酸钾体系中 ,用甲基异丁基甲酮萃取基体锌[3] ,在 ｐＨ 5.6用 1 苯基 3 甲基 4 苯甲酰基 吡唑酮 5(ＰＭＢＰ)萃取稀土元素 (此种合金中仅含稀土元素镧和铈 ) ,在有机相用Ｖ5+将Ｃｅ3+氧化为Ｃｅ4 +后 ,ｐＨ 2 .4甲酸反萃Ｌａ3+至水相 ,然后再用 ｐＨ 2 .4甲酸 抗坏血…     

二(2-乙基己基)磷酸与二(1-甲基庚基)磷酸对稀土元素萃取性能的比较

二(2-乙基己基)磷酸对轻稀土元素及钐-钕、铽-钆的萃取分离系数较大,是稀土萃取工艺中较普遍应用的一种酸性磷型萃取剂,但是它对中稀土(铕-钐,钆-铕)及重稀土(钇-钬、铒-钇)的萃取分离系数则不够大,而且具有萃取容量小、易乳化等缺点,因此寻找高选择性、高容量的新型萃取剂是稀土萃取化学研究的一项重要任务.     

HEH(EHP)-煤油-HCl-RECl_3体系单一稀土的萃取平衡

HEH(EHP)(2-乙基己基膦酸单2-乙基己基酯)作为萃取剂,萃取分离稀土的研究结果表明,HEH(EHP)有较高的分离系数,是一种有效的稀土分离萃取剂。为深入了解HEH(EHP)对稀土元素的萃取性能,以便提供萃取分离工艺的设计参数,我们研究了HEH(EHP)-煤油-HCl-RECl_3体系在不同初始条件下,15个单一稀土的萃取平衡数据,     

稀土萃取分离过程自动控制研究现状及发展趋势

在简要描述稀土萃取分离生产过程的基础上,综述了目前国内外稀土萃取分离过程中稀土元素成分在线检测的方法、装置及其应用现状;稀土串级萃取分离生产过程的计算机流程模拟以及稀土萃取生产过程的自动控制方法、技术及其应用现状.指出了稀土元素组分含量的软测量方法,以综合生产指标为目标的稀土萃取分离生产过程优化控制方法以及由生产过程管理系统和过程控制系统两层结构组成的稀土萃取分离生产过程综合自动化系统已成为稀土萃取分离生产过程自动化未来发展的方向.     

二(2-乙基已基)膦酸萃取色谱分离稀土的研究

研究了以H[DEHP] 试剂为固定相,盐酸、硫酸为流动相,萃取柱色谱分离稀土。稀土元素间的平均分离系数β_(HCl)为3.79,β_(H_2SO_4)为4.57,HCl体系和H_2SO_4体系的β_(La)-Ca分别高达28.5和26.3,其洗脱酸度很低,只是HEH[EHP]体系的1/10～1/14。     

白云鄂博稀土矿联动萃取分离流程的经济技术指标比较

稀土联动萃取工艺以两出口工艺为设计基础。第一模块对原料进行了预分离,第二模块充分利用了稀土元素间的交换功能,省去了第一分离段的反萃及最后分离段的皂化工序。由于其具有酸碱消耗量低、操作方便、废水产生量小等特点,近年来被越来越多稀土分离企业所青睐。针对以氟碳铈和独居石混合矿为代表的白云鄂博稀土矿,根据生产实践经验和目前市场所需要的产品结构,提出了几种可行的P507-HCl体系联动萃取工艺流程。通过比较各联动工艺流程及传统两出口工艺流程的槽体级数、混合室容积大小、有机相和稀土存槽量、盐酸及液碱单耗、废水产生量,找出最优切割方式或联动模式,从而为白云鄂博稀土矿的联动萃取分离提供更优化工艺流程。     

2—氨基苯并噻唑萃取铑及铑,铱分离的研究

本文研究用２－氨基苯并噻唑（简写ＡＢＴ）溶剂萃取铑的最佳条件，在ＫＩ存在下于ｐＨ１～３，加热６０ｍｉｎ，所形成的络合物能定量地被己烷萃取，贱金属离子如Ｆｅ＾３＋，Ａｌ＾３＋，Ｃｕ＾２＋，Ｃｄ＾２＋，Ｃｏ＾２＋，Ｎｉ＾２＋，Ｚｎ＾２＋，Ｍｎ＾２＋，Ｃａ＾２＋，Ｍｇ＾２＋及铂族离子Ｐｔ（Ⅳ），Ｉｒ（Ⅳ）不被萃取，Ｐｄ＾２＋，可在未加入ＫＩ之前预先萃取分离，斜率测得萃合物组成为ＲｈＩ３（ＡＢＴ），红外光     

N，N′-二甲基-N，N′-二己基-3-氧戊二酰胺萃取镧系元素的研究

溶剂萃取因反应速度快,分离效果好,已成为国内外分离提纯稀土的主要方法[1～3].在稀土元素的萃取分离中,为了提高萃取效率,从高放废液中分离、除去锕系和镧系元素从而实现选择性分离,首要问题是选择结构合适的萃取剂和萃取条件[4].由于酰胺类萃取剂具有螯合性能,对Ln(Ⅲ)、An(Ⅲ,Ⅳ,Ⅵ)和碱土金属都有良好的萃取能力,而且此类化合物耐辐射,不易水解,能够燃尽,不产生二次污染,是～种比较有发展前途的萃取剂,在核燃料后处理方面展示较好的应用前景[5～7].     

N,N,N′,N′-四丁基丙二酰胺萃取Tb(Ⅲ)的研究

取代酰胺类萃取剂因其易合成、分解产物易除去而不影响萃取工艺流程等优点 ,在核燃料后处理方面显示出很好的应用前景。国内外在该类萃取剂萃取铀 (Ⅵ )、钍 (Ⅳ )以及硝酸的性能研究方面已经做了大量工作[1 ,2 ] ,但对高放废液中共存稀土元素的萃取研究报道较少[3] 。本文报道Ｎ ,Ｎ ,Ｎ′ ,Ｎ′ 四丁基丙二酰胺 (ＴＢＭＡ)在不同稀释剂中萃取Ｔｂ(Ⅲ )的性能。1　实验1 1　试剂和仪器试剂均为ＡＲ级。ＴＢＭＡ实验室合成 ,减压蒸馏提纯 ,经元素分析、红外光谱等检验产品为目标产物 ,纯度高于 98%。ＦＴＳ 1 65红外光谱仪 (美国Ｂｉｏ Ｒ…     

新试剂1-(2,6-二溴-4-硝基苯)-3-(4-硝基苯)-三氮烯与汞的显色反应及应用

三氮烯试剂与第ＩＢ、ＩＩＢ族金属元素有高灵敏的显色反应 1 [1] ,可用来测定样品中微量的Ｃｄ2 + 、Ｈｇ2 + 、Ｚｎ2 + 、Ｎｉ2 + 。随着表面活性剂引入该显色体系 ,使该试剂与金属离子显色反应的灵敏度有了很大的提高。目前报道的三氮烯显色剂与Ｈｇ2 + 显色反应的灵敏度一般在ε =1 .0× 1 0 5Ｌ·ｍｏｌ-1·ｃｍ-1左右 ,但也有部分试剂的灵敏度较高 ,如ＯＣ Ｃａｄｉｏｎ[2 ] 的ε =1 .77× 1 0 5Ｌ·ｍｏｌ-1·ｃｍ-1,ＤＮＡＡＢ[3 ] ε=1 .74× 1 0 5Ｌ·ｍｏｌ-1·ｃｍ-1,ＭＤＡＡ[4]的ε=1 .8× 1 0 5Ｌ·ｍｏｌ-1·ｃｍ-1,ＡＰＤ…     

Recycling of polymeric composites

For material recycling, composites have to be separated into their components, as only non-mixed raw materials can grant high quality standards. A combined mechanical and subsequent electrostatic separation can be classified as highly economic because it is a dry treatment. This is demonstrated on wire scrap. The separated copper and synthetic materials are obtained in a high degree of purity. Chemical disaggregation of composites has been worked out with medicinal blister packs and beverage packs. Two methods of separation were used: separating the plastic-aluminium composite by dissolving the plastic material or dissolving the adhesive that bonds together the plastic and aluminium. To demonstrate the technical feasibility of the processes, a pilot plant with a capacity of up to 25 tons of blister pack material per year was built. Chemical separation with non-problematic aqueous media was demonstrated with flocked plastics. When integrating composites into chemical processes, questions concerning material specification as well as preparation and chemical utilization must be answered. Mechanical preparation of appropriate raw materials has been exemplified by mixed packing waste, carpet-floor waste, and synthetic material from electrical waste. After the raw materials were analyzed and studies of their quantity and compositions were made, their possible re-use as raw material within a chemical process has been elaborated.     

反相液相色谱对多肽的分离、纯化与制备

用反相高效液相色谱（RPLC）对两种化学合成多肽－－32肽和21肽进行了分离、纯化和制备。在用分析型RPLC色谱柱对多肽样品的制备过程中，对其进样量和洗脱梯度进行了选择。每次进样量为5mg，在最优化色谱条件下，用RPLC一步就可对21肽进行分离纯化，其纯度达到98.6%。而32肽由于样品组分更加复杂，RPLC一步纯化后其纯度仅有80％。通过对色谱分离条件的再次优化，对32肽进行二次分离纯化，纯度达杂，RPLC一步纯化后其纯度仅有80％。通过对色谱分离条件的再次优化，对32肽进行二次分离纯化，纯度达到96.4%。在其最优化条件下，通过多次样品收集和冷冻干燥，分别制备了高纯度的21肽和32肽各100mg。     

两步法提取笼内金属富勒烯

两步法提取笼内金属富勒烯郝春雁，刘子阳，徐文国，郭兴华，刘淑莹（中国科学院长春应用化学研究所，吉林大学化学系，长春，１３００２２）关键词金属富勒烯，索氏提取，ＤＥＩ－ＭＳ，ＬＤＩ－ＭＳ目前笼内包含金属的富勒烯化合物以其新颖独特的结构和性质而格外引人注...     

系列大环草酰胺配合物的合成与表征——推荐一个综合化学实验

采用加热回流和溶剂热两种方法合成了三种大环草酰胺系列配合物,并对所得配合物进行单晶结构解析。使用元素分析、红外光谱、电子光谱、ESR谱对配合物进行了表征和性质研究。该实验原料简单易得,实验方法简便易行,可操作性强,有利于培养学生的实践能力和创新能力。     

可调移动重叠分离图法用于高效液相色谱多台阶梯度分离条件优化的研究

计算机辅助高效液相色谱（HPLC）分离条件优化可以低成本、快速地得到优化的分离条,因而已较为广泛地用于复杂样品的分离分析。基于移动重叠分离图方法,又发展了一种新型的多台阶梯度分离条件的优化方法可调移动重叠分离图法。该方法通过预测不同流动相条件下各组分的保留时间、峰宽和分离度,绘制出对于样品中各组分的重叠分离区域图。在对当前台阶流动相组成进行优化的同时,考虑其对后面一到两个台阶上流出组分保留的影响,实时地重新绘制对于后面台阶上流出组分的重叠分离区域图。通过观察当前台阶流动相条件对当前台阶和后面台阶上流出组分分离的影响,综合考虑样品中所有组分的分离情况,找到更接近全局最优的分离条件。通过扫描的方法对优化得到的分离条件进行微调,能够进一步提高分离效果。采用文献数据对可调移动重叠分离图法的应用加以说明,在二元流动相体系下,证明了该方法在HPLC方法建立方面的优越性。     

Quantitative determination of fluoride as a major pollutant in the emissions from the thermal treatment of clayey raw materials

Three clayey raw materials for production of traditional ceramics, all with medium to high fluorine content, have been investigated for determining their attitude to fluoride emission during firing, at varying parameters of the firing cycle, maximum firing temperature included, and in the presence or in the absence of calcium carbonate either added to the sample or naturally present in it. Different analytical methods for the determination of fluoride have been tested, together with different sample preparation procedures aimed to obtain minimum loss of fluoride in the pre-treatment step.     

MSPD Extraction of Sulphonamides from Meat followed by LC Tandem MS Determination

In this paper an extraction procedure is presented for sulphonamides (SAs) in animal tissues (raw meat and meat-based baby food), based on matrix solid phase dispersion (MSPD). Determination was carried out using liquid chromatography coupled with tandem mass spectrometry. In complex matrices extraction is usually the critical step of analysis: several procedures were employed for the recovery of SAs in animal tissues, but often they entail time and solvent-consuming processes. MSPD has demonstrated itself to be a very efficient extraction technique for matrices such as animal tissues, with simplified and shortened procedures, and very low solvent consumption. This procedure allowed to obtain quantitative recovery, high selectivity improved by a cool eluant, and easy application. Good recoveries are accompanied by low RSDs and not a significative matrix effect. The MSPD procedure, coupled with LC-MS-MS analysis, provides very interesting LODs, due also to the concentration step. Validation is carried out following the EU guidelines for confirmation methods (EU Dec. 657/02).     

On the Possibility of Separation of Ammonium Bisulfate into Sulfate and Acid in the Cyclic Salt-Type Processing of Alumina-Containing Raw Materials

The bisulfate process is promising for the development of closed cycle technologies for the processing of alumina-containing raw materials with reagent recovery. Implementing this process requires a rational method for separation of ammonium bisulfate into the sulfate and sulfuric acid in each cycle. The possibility of such separation was shown for the first time by modification of the acid retardation technique based on the sieve effect in the nanoporous medium. The proposed method solves the problem of reagent recovery, which is relevant for some industrial processes, and has prospects for the development of new ore processing techniques.     

Large-scale computational screening of zeolites for ethane/ethene separation

Large-scale computational screening of thirty thousand zeolite structures was conducted to find optimal structures for separation of ethane/ethene mixtures. Efficient grand canonical Monte Carlo (GCMC) simulations were performed with graphics processing units (GPUs) to obtain pure component adsorption isotherms for both ethane and ethene. We have utilized the ideal adsorbed solution theory (IAST) to obtain the mixture isotherms, which were used to evaluate the performance of each zeolite structure based on its working capacity and selectivity. In our analysis, we have determined that specific arrangements of zeolite framework atoms create sites for the preferential adsorption of ethane over ethene. The majority of optimum separation materials can be identified by utilizing this knowledge and screening structures for the presence of this feature will enable the efficient selection of promising candidate materials for ethane/ethene separation prior to performing molecular simulations.     

可变色形状记忆材料

以聚乙烯醇和单宁酸为原料制备出了形状记忆水凝胶,以乙二胺四乙酸、二水合氯化铜、六水合氯化镁、氧化铝为原料制备出了无机热致变色材料,以结晶紫内酯、硼酸、十六醇为原料制备出了有机热致变色材料,并将形状记忆材料与热致变色材料结合,成功制备出了两种既能记忆形状又能变色的新型复合高分子材料。本实验原料简单易得,方法简便,并与本科阶段有机化学、无机化学、仪器分析、精细化学品化学等课程中所学习的自由基聚合反应、化学交联、络合反应等知识结合,可作为本科教学的一个综合实验,提高学生的动手能力,激发学生学习化学的兴趣和热情。