HEH/EHP在中空纤维膜器中萃取钕、钐及传质研究

２－乙基己基膦酸单２－乙基己基酯（ＨＥＨ／ＥＨＰ,ＨＬ）是广泛用于稀土分离湿法冶金的有效萃取剂［１～３］．未氨化的ＨＥＨ／ＥＨＰ在中空纤维膜（ＨＦＭ）中萃取稀土元素的机理和控制模式已有报道［４,５］,但未氨化的ＨＥＨ／ＥＨＰ对轻、中稀土的萃取能力较弱...     

共聚型2—乙基己基膦酸单2—乙基己基酯萃淋树脂孔结构与分离效？…

应用性能优良的２－乙基己基膦酸单２－乙基己基酯ＨＥＨ（ＥＨＰ）萃取剂，首次制备了一系列不同孔结构的萃淋树脂，针对难以分离的镧系元素最难分离的镨，钕，研究了孔结构等与分离效能之关系，探寻出最适宜的孔结构，其比表面积Ｓ为２０９ｍ＾２／ｇ，平均孔径为７．７ｎｍ孔体积Ｖｇ０．４０１ｍＬ／ｇ；ＨＥＨ（ＥＨＰ）最适宜量为４６．５％，从而达到最佳分离。     

Ga^3＋的新萃取体系的界面特性和胶团化作用研究

研究了Ｇａ~（３＋）协萃体系（Ｇａ~（３＋）－Ｄ_２ＥＨＰＡ－Ｈ_２ＭＰＡ－正十二烷－Ｈ_２ＳＯ_４）的界面吸附和胶团形成热力学，发现该萃取体系中［Ｈ_２ＭＰＡ］影响Ｄ_２ＥＨＰＡ和Ｈ_２ＭＰＡ的界面吸附性质。在中、高［Ｈ_２ＭＰＡ］范围内Ｄ_２ＥＨＰＡ与Ｈ_２ＭＰＡ的界面吸附行为相反，Ｄ_２ＥＨＰＡ的存在也影响Ｈ_２ＭＰＡ的界面吸附行为。研究了界面张力与各因素关系的数学模型，并获得某些胶团形成和界面吸附特性的物化参数。     

共聚型2-乙基己基膦酸单2-乙基己基酯萃淋树脂孔结构与分离效能的关系

应用性能优良的２－乙基己基膦酸单２－乙基已基酯ＨＥＨ（ＥＨＰ）萃取剂，首次制备了一系列不同孔结构的萃淋树脂，针对难以分离的镧系元素中最难分离的镨、钕，研究了孔结构等与分离效能之关系，探寻出最适宜的孔结构。其比表面积Ｓ为 ２０９ ｍ２／ｇ，平均孔径为 ７．７ｎｍ，孔体积Ｖｇ ０．４０１ｍＬ／ｇ；ＨＥＨ（ＥＨＰ）最适宜量为４６．５％，从而达到最佳分离。     

2－乙基己基膦酸单（2－乙基己基）酯从盐酸溶液中萃取Ga（Ⅲ）的机理

２－乙基己基膦酸单（２－乙基己基）酯从盐酸溶液中萃取Ｇａ（Ⅲ）的机理赵经贵，邢美君，刘宏（黑龙江大学化学系哈尔滨１５００８０）关键词溶剂萃取，镓，乙基己基膦酸单（乙基己基）酯２－乙基己基膦酸单（２－乙基己基）酯（Ｐ５０７，ＥＨＰ）在稀有元素、有色金属...     

HDEHP萃取Ga（Ⅲ）的动力学

用生长液滴法研究了ＨＤＥＨＰ在盐酸介质中萃取Ｇａ（Ⅲ）的动力学，结果表明，萃取反应速率取决于发生在界面区域内两步连续反应Ｇａ３＋＋Ａｉ－＝ＧａＡｉ２＋ＧａＡｉ２＋＋Ａｉ－＝ＧａＡ２＋ｉ研究了阴离子表面活性剂ＳＤＳ、ＡＢＳ对ＨＤＥＨＰ萃取Ｇａ（Ⅲ）的影响，二者均不改变ＨＤＥＨＰ萃取Ｇａ（Ⅲ）的分配比，但使其正向萃取初始速率降低，原因是表面活性剂与萃取剂在界面上发生了竞争吸附；其次是表面活性剂的加入导致了界面膜上分子排列更致密和界面膜增厚，产生了更大的传质阻力。     

P204萃取剂皂化过程中的物理化学性质及相区变化

Ｐ２０４萃取剂皂化过程中的物理化学性质及相区变化曾平,王贵清（湘潭大学化学系,湘潭,４１１１０５）关键词皂化Ｐ２０４萃取剂,物理化学性质,相区,微乳状液二－（２－乙基己基）磷酸（简称Ｐ２０４或ＨＡ）是一种良好的工业螫合萃取剂,在湿法冶金中得到广泛应用...     

2－乙基己基膦酸单2－乙基己基酯萃取镧系元素的NMR研究

本研究测定了２－乙基己基膦酸单２－乙基己基酯（ＨＥＨ／ＥＨＰ）与镧系元素镧、铈、镨、钕、钐、铕、钬、铒、镱、镥的１Ｈ、（１３）Ｃ、（３１）Ｐ核磁共振谱。对ＨＥＨ／ＥＨＰ的碳骨架进行了详细归属，并根据（３１）ＰＮＭＲ谱峰的积分面积，推测了萃合物可能的配位络合比，（ＨＥＨ／ＥＨＰ与Ｌｎ（Ⅲ）之比）。对铕、镱、镥为６，对铒为５，对钬、钐为４。     

二(2-乙基己基)磷酸对氨基酸的萃取平衡

二（２－乙基己基）磷酸对氨基酸的萃取平衡曹汉瑾,王德宝,刘沛妍,吴子生,严忠（东北师范大学化学系,长春,１３００２４）关键词氨基酸,二（２－乙基己基）磷酸,萃取平衡,分配比迄今为止,有关氨基酸溶剂萃取的文献报道还不多［１～３］．本实验以二（２－乙基己...     

二（2—乙基已基）磷酸从含氟稀土硫酸溶液中萃取铈的机制

研究了二（２－乙基已基）磷酸（ＤＥＨＰＡ）－磺化煤油体系从氟碳铈矿氧化焙烧－硫酸浸出液中萃取Ｃｅ＾４＋的机制,发现水相中Ｆ＾－和Ｃｅ＾４＋同时被萃入有机相,通过斜率法和研究平衡有机相中ｃＦ－／ｃＣｄ＾４＋和初始水相酸度、初始水相氟离子浓度、有机相浓度之间的关系,推测出Ｆ＾－和Ｃｅ＾４＋以ＣｅＦ２Ａ２形式被ＤＥＨＰＡ萃入有机相。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.