409 resultados para Robot SCORBOT III - ER
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
A series of novel, colorless, and transparent sot-gel derived hybrid materials Ln-DBM-Si covalently grafted with Ln(DBM-OH)(3)center dot 2H(2)O (where DBM-OH = o-hydroxydibenzoylmethane, Ln = Nd, Er, Yb, and Sin) were prepared through the primary beta-diketone ligand DBM-OH. The structures and optical properties of Ln-DBM-Si were studied in detail. The investigation results revealed that the lanthanide complexes were successfully in situ grafted into the corresponding hybrids Ln-DBM-Si. Upon excitation at the maximum absorption of ligands, the resultant materials displayed excellent near-infrared luminescence.
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本文分另研究了H[DEHP]从不同酸性介质中萃取稀土(III)(Sc、Y、Ho、Er、yb、Lu)及Fe(III)、Zn(II)的机理及性能。一、H[DEHP]从 H_2SO_4介质中萃取Sc(III)的机理 1. H[DEHP]萃取H_2SO_4及其机理 2. H[DEHP]萃取Sc(III)的机理,用斜率法和饱和法确定了H[DEHP]的正庚烷溶液从H_2SO_4溶液中萃取Sc_2(SO_4)_3的机理及萃合物组成。研究表明,H[DEHP]萃取Sc(III)在高、低两种酸度范围内存在着两种不同的萃取机理。二、H[DEHP]从HCl介质中萃取Ln(III)和Fe(III)的性能及H[DEHP]萃取Ln(III)的机理研究了H[DEHP]的正庚烷溶液从HCl介质中萃取稀土(III)(Sc、Y、Ho、Er、Yb、Lu)和Fe(III)的性能,得出H[DEHP]在相同条件下萃取以上各金属离子的顺序是:Sc(III)>Fe(III)>Lu(III)>Yb(III)>Er(III)>Y(III)>Ho(III), 并计算了各金属离子之间的分离因素(β)。文中还讨论了Sc(III)、Fe(III)、Lu(III)之间的分离以及重稀土离子间的萃取分离,同时与相同实验条件下HEH[EHP]的萃取性能进行了比较,为新的萃取体系提供了一些参数。三、H[DEHP]从不同介质中萃取Fe(III)的机理,研究了H[DEHP]的正率烷溶液从Hcl介质中和H[DEHP]的正庚烷溶液从H_2SO_4介质中萃取Fe(III)的平衡规律;用斜率法、饱和法以及IR和NMR谱等讨论了低酸度下的萃取机理。四、H[DEHP]萃取Zn(II)的机理,研究了H[DEHP]的正率烷溶液从Hcl介中萃取Zn(II)的平衡,利用斜率法、饱和法及SR、NMR谱等讨论了低Hcl浓度下的萃取机理。
Resumo:
溶剂萃取是分离稀土元素的主要方法。通过对溶剂萃取动力学的研究,不但能够从理论上深入了解萃取过程的反应机理。而且在萃取的实际应用中,也可以利用动力学因素提高分离效率和选择性。因此,稀土元素(III)和铁(III)的萃取动力学研究,对萃取机理和实际应用都具有重要意义。本文用液滴生长法分别研究了伯胺N_(1923)萃取稀土(III)及铁(III)和HEH(EHP)萃取稀土(III)的动力学。1、研究了伯胺盐(N1923H)_2SO_4从硫酸介质中萃取La(III)和Fe(III)的动力学过程。考察了La~(3+),Fe~(3+),N1923,H~+,SO_4~(2-)和温度对萃取速率的影响。结果表明,(N1923H)_2SO_4萃取La(III)和Fe(III)时,它们之间在动力学性质上差异不大。并根据实验结果,推测了萃取反应机理。推导了正向初始萃取速率的理论方程。计算了萃取反应的表观活化能。2、研究了HEH(EHP)从HCL-NaCl-NaNO_3溶液中萃取Er(III)的动力学过程。考察了Er~(3+),HEH(EHP),NO_3~-,CL~-,H~+和温度对萃取速率的影响。结果表明,在HEH(EHP)从盐酸介质中萃取Er(III)时,NO_3~-能增加该萃取体系的萃取速率。并根据实验结果,当NaNO_3作为添加剂时,推测了萃取反应机现。导出了正向初始萃取速率的理论方程。计算了萃取反应机理。导出了正向初始萃取速率的理论方程。计算了萃取反应的表观活化能。提出影响萃取速率的“表面张力效应”。3、研究了HEH(EHP)-N1923-正庚烷萃取体系从盐酸介质中萃取Er(III)的动力学过程。考察了Er~(3+),HEH(EHP),N1923,CL~-,H~+和温度对萃取速率的影响。结果表明,在盐酸介质中HEH(EHP)萃取Er(III)时,N1923对该萃取体系的萃取速率有影响。适当浓度的N1923能加快萃取速率。当N1923作为表面活性剂时,根据实验结果推测了萃取反应机理。推导了正向初始萃取速率的理论方程。计算了萃取反应的表观活化能。4、研究了HEH(EHP)从HCl-NaCl-KSCN溶液中萃取Er(III)的动力学过程。考察了Er~(3+),HEH(EHP), CL~-,SCN~-,H~+和温度对萃取速率的影响。结果表明,在HEH(EHP)从盐酸介质中萃取Er(III)时,硫氯酸盐能加快该体系的萃取速率,起着正催化作用。当KSCN作为催化剂时,根据实验结果推测了萃取反应机理。推导了正向初始萃取速率的理论方程。计算了萃取反应的表观活化能。
Resumo:
Extraction resins, of the type of;levextrel, (which is a collective term for styrene/divinylbenzene based copolymers of predominantly macroporous structure that contain a selective extractant) are important for the recovery and separation of metal ions, as they combine features of solvent extraction and ion exchange resins. This paper presents the results of the adsorption of heavy rare earth ions (Ho(III), Er(III), Tm(III), Yb(III), Lu(III) and Y(III)) from hydrochloric acid solutions at 0.2 mol/L ionic strength and 50 degrees C by the extraction resin containing di (2,4,4-trimethyl pentyl) phosphinic acid (Cyanex 272) and the chromatographic separation of (Er(III), Tm(III) and Yb(III)). Technological separation products, with purity and yield of Tm2O3 >99.97%, >80%, Er2O3 >99.9%, >94% and Yb2O3 >99.8%, >80% respectively, have been obtained from a feed having the composition Tm2O3 60%, Er2O3 10%, and Yb2O3 3%, the others 27%. The distribution coefficients, extraction equilibrium constants and separation factors have been determined as a function of acidity, loading of the resin and rare earths, flow rates and column ratios. The resolutions and efficiencies of separation of Er/Tm/Yb each other have been calculated. The stoichiometry of the extraction of rare earth ions has been suggested as well.
Resumo:
环烷酸是一种价廉容量大的萃取剂,在其中加入混合醇工业上已用于分离制取高纯Y_2O_3,并用于提纯氧化铕。为了扩大环烷酸的应用,我们对加有中性磷萃取剂及β-双酮类螯合剂的环烷酸协萃体系进行了较为系统的研究。测定了协萃体系萃取Nd(III)和Er(III)的协萃曲线,协萃剂的协萃能力强弱顺序为:PMBP>TOPO>BDBP>DBBP>TBP Er(III)>Nd(III) TBP几乎没有协萃效应,当其在有机相中所占克分子而分数大于30%时,尤其如此,DBBP有类似的规律,其余协萃剂均无反协萃效应。测定单一稀土离子分配比随原子序数的变化可见协萃体系协萃重稀土的能力大于轻稀土。钇的萃取位置发生了显著的变化,主要是位于轻稀土组,在如有DBBP及TOPO的体系中移至了HO附近;随着平衡水相酸度的降低,钇有向原子序数增大的方向移动的趋势,而且中性磷萃取剂的萃取能力越大,钇的萃取位置变化越多,使其和镧系元素之间的分离因素有所下降。用解析法等研究了多元协萃络合物的组成及协萃反应机理,并计算了相应的表观协萃平衡常数及有机相加合反应平衡常数。考察萃取前后有机相的红外光谱可见中性磷萃取剂和环烷酸形成氢键的能力为:TBP>DBBP>BDBP>TOPO和金属离子的配位能力为:TBP<DBBP<(BDBP)<TOPO Nd(III)<Er(III)找出了环烷酸配位后羧基的反对称及对称伸展振动,由二者之差指出羧基为螯合配位或双金属格式配位,P=O和金属离子形成了配价键。游离中性磷化合物,混合有机相中及协萃络合物中的P=0伸展振动波数与其诱导效应指数之间符合线性规律。将中性磷化合物单独萃取Nd(III)及Er(III)时的分配比,协萃体系的总分配比,酸性协萃系数,表现协萃平衡常数及有机相加合反应平衡常数的对数对P=0伸展振动频率及诱导效应指数作用,也能找到近似的线性规律。分析环烷酸和PMBP混合前后的振动光谱及换磷共根~1H谱发现环烷酸和PMBP之间也有氢键律合作用。为了进一步说明协萃剂在萃取过程中的作用,合成了除Pm以外十五个稀土-PMRP-环烷酸三元络合物。用快原子轰出质谱法测定了La、Pr及Er等元素络合物的分子量。络合物TG-DTA曲线表明分解过程分两步进行,第一步为环烷酸的分解,第二步为PMBP的分解,最后产物为氧化物。环烷酸首先分解是由于环烷酸和稀土离子的键合强度不如PMBP,这在络合物的质谱,~1HNMR谱及恒温产物的红外光谱中均得到了证实,系统地研究了络合物在4000-100cm~(-1)范围内的FT-IR艺谱,分析了配体和稀土离子配位前后,COOH,ezo, c…e…c及RE-O等振动附近的变化,指出了配体和稀土离子之间的配位形式可能为:PMBP和稀土离子形成的RE-O键伸展振动频率可分为轻重稀土组,环烷酸和稀土离子之间的RE-O键伸展振频率与稀土离子总轨道角动量之间符合斜“W”规律,为常数和原子序数之间呈现近似“四分组”效应,钇位于Lu前,并接近于Lu。还考察了络合物~1HNMR谱上配体的各种基团质子化学位移,指出络合物可能有两种空间模型。在所形成的化合物中,Ce呈现四价状态为Ce(PMBP)_2A_2,其稳定性大于其他三价稀土离子的络合物。
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本文研究了酸性磷(膦)类萃取剂:二(2,4,4-三甲基戊基)膦酸(C272)、仲丁基膦酸2-丁基辛基酯(J040)、仲已基膦酸2-丁基辛基酯(J043)对三价稀土离子的萃取及分离性能,测定了相邻元素间在不同pH范围内的平均分离系数,讨论了C272、J040、J043萃取Sc(III)、Er(III)、Ta(III)、Ho(III)的机理,合成了J040与La(III)、Ho(III)、Y(III)、Er(III)、Cd(III)、Pb(III)的固体配合物,并对其结构进行了表征。本文还以2-乙基乙基膦酸单2-乙基已基酯(P507)为萃取剂,利用分馏串级萃取,进行了低损耗红外光纤原料的提纯研究。一、不同结构的酸性磷(膦)酸酯对三价稀土离子的萃取。二、不同结构酸性磷(膦)酸酯萃取Er(III)、Tr(III)、Ho(III)、Sc(III)的机理。本实验还考察了平衡水相酸度对萃取平衡的影响,由酸度曲线求出了一些元素对间在不同pH范围内的平均分离系数;根据萃取剂浓度对萃取平衡的影响结果分别求出了各萃取平衡反应的浓度平衡常数;研究了温度对萃取平衡的影响,由此求出了萃取平衡反应的热力学函数。对C272,还考察了萃取分配比随原子序数的变化规律。结果表明具有明显的四分组效应。
Resumo:
A kind of solvent (ionic liquid) impreganated resin (IL-SIR) was developed herein for ameliorating imidazolium-type IL-based liquid-liquid extraction of metal ions. In this study, [C(8)mim][PF6] containing Cyanex923 was immobilized on XAD-7 resin for solid-liquid extraction of rare earth (RE). The solid-liquid extraction contributed to ameliorating mass transfer efficiency, i.e. shortening equilibrium time from 40 min to 20 min, increasing extraction efficiency from 29% to 80%. In additional, the novel IL-SIR could separate Y(III) from Sc(III), Ho(III), Er(III), Yb(III) effectively by adding water-soluble complexing agent.
Resumo:
This paper presents the results of the adsorption of heavy rare earth ions (Gd(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III), Lu(III) and Y(III)) from hydrochloric acid solutions at 30 degreesC by the extraction resin containing 1-hexyl-4-ethyloctyl isopropylphosphonic acid (HEOPPA), which has higher steric hindrance, higher selectivities and lower extraction and stripping acidity than di(2-ethylhexyl)phosphoric acid (DERPA) or 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (HEH/EHP). The dependence of acid concentration, flow rate and amounts of rare earth ions sorbed on the separation of Er-Tm, Tm-Yb and Er-Tm-Yb mixtures has been studied. The baseline chromatographic separation of Er-Tm-Yb mixture has been observed. Satisfactory results with purity and yield of Tm2O3>99.71% and >71.25%, Er2O3>99-81% and >94.17%, and Yb2O3>99.74% and >89.83%, respectively, have been obtained. The parameters such,as resolution, separation factors and efficiencies have been determined as a function of acidity, loading of rare earth elements and flow rates. The stoichiometry of the extraction of rare earth ions has been suggested as well.
Resumo:
Seven trivalent lanthanide perchlorate complexes of the types [Ln(bphab)(4)ClO4] (ClO4)2 (where La = La(III), Pr(III), Nd(III) and Eu(III)) and [Ln(bphab)(3)ClO4] (ClO4)(2) (where Ln = Ho(III), Er(III) and Lu(III), and bphab = 1,4-bis(phenylsulfinyl)butane) have been synthesized by the reaction of bphsb with lanthanide(III) perchlorate in methanol-chloroform mixture. The complexes have been characterized by elemental analyses, molar conductance, electronic and infrared spectral techniques. Several bonding parameters have been calculated from the absorption spectra of the Pr(III), Nd(III), Ho(III) and Er(III) complexes. Infrared spectral data suggest that bphsb acts as bidentate ligand coordinating through the oxygen atoms of the S=O moieties.
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Six compounds of M2F3 center dot 1.2H(2)O (M=EU, Ga, Tb, Y, Er, LU: H2F=Fumaric acid) have been synthesized. The structures of Eu(III), T b(III), Y(III), Er(III) and Lu(III) compounds have been determined by singal crystal X-ray diffraction method. The complex of Eu(III) crystallizes in tri-clinic space group P (1) over bar, and the coordination number of Eu3+ is ten. The other four complexes crystallize in monclinic space P2(1)/c, and the coordination numbers of the metal ions are eight. Each of the complexes shows a three-dimensional net structures.
Resumo:
A beta-diketone ligand 4,4,5,5,5-pentafluoro-1-(2-naphthyl)-1,3-butanedione (Hpfnp), which contains a pentafluoroalkyl chain, was synthesized as the main sensitizer for synthesizing new near-infrared (NIR) luminescent Ln(pfnp)(3)phen (phen = 1,10-phenanthroline) (Ln = Er, Nd, Yb, Sm) complexes. At the same time, a series of lanthanide complexes covalently bonded to xerogels by the ligand 5-(N,N-bis-3-(triethoxysilyl)propyl)ureyl-1,10-phenanthroline (phen-Si) were synthesized in situ via a sol-gel process. [The obtained materials are denoted as xerogel-bonded Ln complexes (Ln = Er, Nd, Yb, Sm).] The single crystal structures of the Ln(pfnp) 3phen complexes were determined.
Resumo:
New near-infrared-luminescent mesoporous materials were prepared by linking ternary lanthanide (Er3+, Nd3+, Yb3+, Sm3+, Pr3+) complexes to the ordered mesoporous MCM-41 through a functionalized 1,10-phenanthroline (phen) group 5-(N,N-bis-3-(triethoxysilyl)propyl)ureyl-1,10-phenanthroline. The resulting materials (denoted as Ln(hfth)(3)phen-M41 and Pr(tfnb)(3)phen-M41; Ln=Er, Yb, Nd, Sm; hfth = 4,4,5,5,6,6,6-heptafluoro-1-(2-thienyl)hexane-1,3-dionate; tfnb = 4,4,4-trifluoro-1-(2-naphthyl)- 1, 3-butanedionate) were characterized by powder X-ray diffraction, N-2 adsorption/desorption, and elemental analysis. Luminescence spectra of these lanthanide-complex functionalized materials were recorded, and the luminescence decay times were measured. Upon excitation at the absorption of the organic ligands, all these materials show the characteristic NIR luminescence of the corresponding lanthanide (Er3+, Nd3+, Yb3+, Sm3+, Pr3+) ions by sensitization from the organic ligands moiety. The good luminescent performances enable these NIR-luminescent mesoporous materials to have possible applications in optical amplification (operating at 1300 or 1500 nm), laser systems, or medical diagnostics.
Resumo:
The extraction and separation of Ho, Y, and Er(III) with the mixtures of bis(2,4,4-trimetylpentyl)monothiophosphinic acid (Cyanex 302) and another organic extractant, such as acidic organic extractant (di-2-ethylhexyl phosphoric acid P204, 2-ethythexyl phosphoric acid mono-2-ethylhexyl ester P507, di-2-ethylhexyl phosphinic acid P229, and sec-nonylphenoxy acetic acid CA-100), neutral organic extractant (tri-n-butyl phosphate TBP, di-(1-metylheptyl)metyl phosphate P350, and branched trialkylphosphinic oxide Cyanex 925) or primary amine N1923, has been investigated in this paper. The extractability and separation ability for the Ho, Y, and Er with the mixtures of Cyanex 302 and organic extractants has been compared. The synergistic effect of the Ho, Y, and Er extraction with the mixtures of Cyanex 302 and P229, Cyanex 925, CA-100, or N1923 has been explored and the synergistic enhancement coefficients have been calculated. At last, the Y3+ synergistic extraction with the mixtures of Cyanex 302 and CA-100 has been determined and the extracted complex has been deduced.
Resumo:
The ligand Hhfth [4,4,5,5,6,6,6-heptafluoro-1-(2-thienyl)hexane-1,3-dione], which contains a heptafluoropropyl group, has been used to synthesize several new ternary lanthanide complexes (Ln = Er, Ho, Yb, Nd) in which the synergistic ligand is 1,10-phenanthroline (phen) or 2,2'-bipyridine (bipy). The two series of complexes are [Ln(hfth)(3)phen] [abbreviated as (Ln)1, where Ln = Er, Ho, Yb] and [Ln(hfth)(3)bipy] [abbreviated as (Ln)2, where Ln = Er, Ho, Yb, Nd]. Members of the two series have been structurally characterized. The growth morphology, diffuse reflectance (DR) spectra, thermogravimetric analyses, and photophysical studies of these complexes are described in detail. After ligand-mediated excitation of the complexes, they all show the characteristic near-infrared (NIR) luminescence of the corresponding Ln(3+) ions (Ln = Er, Ho, Yb, Nd). This is attributed to efficient energy transfer from the ligands to the central Ln(3+) ions, i.e. an antenna effect. The heptafluorinated substituent in the main hfth sensitizer serves to reduce the degree of vibrational quenching. With these NIR-luminescent lanthanide complexes, the luminescent spectral region from 1300 to 1600 nm, which is of particular interest for telecommunication applications, can be covered completely.
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The rate of extraction of Er(III) from aqueous acetate solutions at 0. 2 mol/L ionic strength by HBTMPTP in n-heptane was studied by using a constant interfacial area cell with laminar flow at (30+/- 0. 5)degrees C. The interfacial activity of HBTMPTP was investigated at n-heptane/0. 2 mol/L (H, Na)Ac (pH=5. 00) interface, The rate of Er(III) extraction was measured at different chemical compositions by varying hydrogen ion, HBTMPTP, Cyanex 302 and chlorine ion concentrations, The effect of stirring speed, temperature and special interfacial area on the rate of extraction was also studied. The results showed that, under the conditions of the experiments, the overall rate is diffusion controlled, that the impurities of Cyanex 302 have the effect of synergistic extraction.