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1.
The present research is aimed at the development of D151 resin as an adsorbent that it can be used in the adsorption of Ce(Ⅲ) ions.The adsorption and desorption behaviors of Ce(Ⅲ) on D151 resin have been investigated by chemistry analysis.The influence of operational conditions such as contact time,initial concentration of Ce(Ⅲ),initial pH of solution and temperature on the adsorption of Ce(Ⅲ) had also been examined.The results show that the optimal adsorption condition of D151 for Ce(Ⅲ) was achieved at pH=6.50 in HAc-NaAc medium.The maximum uptake capacity of Ce(Ⅲ) was 392 mg/g resin at 298 K.The adsorption of Ce(Ⅲ) followed both the Langmuir isotherm and Freundlich isotherm,and the correlation coefficients had been evaluated.Even kinetics on the adsorption of Ce(Ⅲ) had been studied.The adsorption rate constant k298 K valued was 1.3×10-5 s-1.The calculation data of thermodynamic parameters which ΔS0 value of 91.34 and ΔH0 value of 7.07 kJ/mol indicate the endothermic nature of the adsorption process.While,a decrease of Gibb’s free energy(ΔG0) with increasing temperature indicated the spontaneous nature of the adsorption process.Finally,Ce(Ⅲ) could be eluted by using 0.5 mol/L HCl solution and the elution percentage was as high as 100%.Adsorption mechanism was also proposed for the adsorption of Ce(Ⅲ) ions onto D151 resin using infrared spectroscopy technique.  相似文献   

2.
N-methylimidazolium functionalized anion exchange resin in NO3-form(RNO3) was prepared and used for adsorption of Ce(IV)in nitric acid medium.The adsorption amount increased with shaking time increasing and the adsorption equilibrium was obtained within 180min.Ce(IV) was partially reduced to Ce(III) and the reduction percent of Ce(IV) increased with shaking time increasing.But RNO3 was morestable than other resins due to the high resistance to oxidation.A little increase of adsorption amount was found with concentration of HNO3increasing.However,the reduction percent of Ce(IV) decreased with the increase of HNO3 concentration.The addition of NaNO3 decreasedthe adsorption amount of Ce(IV) on RNO3 due to the competitive anion exchange reaction.Ce(IV) was adsorbed on RNO3 in the form ofCe(IV) anion nitrato-complex.RNO3 and Ce(IV)-loaded RNO3 were characterized by fourier transform infrared(FT-IR) and thermogravimeric analysis(TGA).Ce(IV) could be easily separated from RE(III) solution by RNO3.  相似文献   

3.
An enhanced adsorption and desorption procedure of Nd(III) onto D113-III resin were prepared with various chemical methods.Batch studies were carried out with various pH,contact time,temperature and initial concentrations,and then column studies were conducted.The results showed that the optimal adsorption condition was at pH value of 6.90.The process was fast initially and arrived equilibriumwithin 60 h.The resin exhibited a high Nd(III) uptake as 232.56 mg/g at 298 K.The adsorption data fitted well with pseudo-second-order kinetic model.Thermodynamic parameters were studied,which indicated that the adsorption process was spontaneous and endothermic.Thomas model was delineated here to predict the breakthrough curves based on the experimental column study data.In the elution test,1 mol/LHCl solution could achieve a satisfactory elution rate,which indicated that D113-III resin could be regenerated and reused.Finally,the IRspectroscopic technique was undertaken,and a novel adsorption mechanism was proposed.  相似文献   

4.
The adsorption and desorption behaviors of Er(Ⅲ) ion on D113-Ⅲ resin were investigated.Batch adsorption studies were carried out with various Er(Ⅲ) ion concentrations,pH,contact time and temperature,indicating that D113-Ⅲ resin could adsorb Er(Ⅲ) ion effectively from aqueous solution.The loading of Er(Ⅲ) ion onto D113-Ⅲ resin increased with increasing the initial concentration.The adsorption was strongly dependent on pH of the medium with enhanced adsorption as the pH turned from 3.45 to 6.75.In the batch s...  相似文献   

5.
The adsorption behaviors of La(Ⅲ) ion on bamboo charcoal were investigated with various chemical methods and IR spectrometry. Parameters studied include the effects of pH,average particle size,initial ion concentration,contact time and temperature by batch method. The results showed that bamboo charcoal could remove La(Ⅲ) ions effectively from aqueous solution. The loading of La(Ⅲ) ions was strongly dependent on pH of the medium and the optimal adsorption condition was in HNO3-TEA medium with pH value of 7.20. In the batch system,the modified bamboo charcoal exhibited the highest La(Ⅲ) ion uptake as 120 mg/g at 298 K,at an initial pH value of 7.20. The adsorption kinetics were tested with Lagergren-first-order model and pseudo-second-order model. The adsorption data were conformed to the Langmuir and Freundlich isotherms,and the correlation coefficients had been evaluated. Thermodynamic parameters such as free energy(ΔG) ,which were all negative,indicated that the adsorption of La(Ⅲ) ion onto bamboo charcoal was spontaneous and the positive value of enthalpy(ΔH) showed that the adsorption was endothermic in nature. Thomas model was applied to experimental column data to determine the characteristic parameters of column useful for process design. The characterization of both before and after adsorption of La(Ⅲ) ion on bamboo charcoal was undertaken using IR spectroscopic technique. The results revealed that bamboo charcoal was a good choice as a biosorbent for the recovery of lanthanum from aqueous solution.  相似文献   

6.
The self-assembly of 5-bromoisophthalic acid (H2BIPA) with Eu(NO3)3·6H2O under the hydrothermal conditions gave a 3D coordination polymer, Eu2(BIPA)3(CH3CH2OH) (1), which was characterized by elemental analysis, IR and single-crystal X-ray diffraction. Complex 1 displayed an unusual three-dimensional network of a rare (4,6)-connected (48.66.8)2(44.62)2(42.84) topology, which was different from Eu2(BDC)3(H2O)2 (BDC=isophthalate), because the -Br substituent of the isophthalate resulted in the different electronic effects and the steric hindrance to change the coordination modes of carboxylate groups in the assembled process. Moreover, the luminescent properties of 1 were also investigated in the solid state.  相似文献   

7.
New complexes of coumarin-3-carboxylic acid(HCCA) with Ho(Ⅲ) and Pr(Ⅲ) were synthesized and their structures and spectral properties were investigated by elemental analysis,IR,Raman and NMR measurements.According to the experimental data the complexes’ formula and geometries were suggested.Vibrational frequencies,IR intensities and Raman activities as well as 1H NMR chemical shifts of HCCA and its Ho(Ⅲ) and Pr(Ⅲ) complexes were presented.The comparative experimental vibrational and NMR analyses of both the ligand and the Ln(Ⅲ) complexes predicted the bidentate binding to Ho(Ⅲ) and Pr(Ⅲ) through the deprotonated carboxylic oxygen and the carbonylic oxygen of the ligand.The cytotoxic/cytostatic properties of the ligand and the newly synthesized complexes of coumarin-3-carboxylic acid with Ho(Ⅲ) and Pr(Ⅲ) were tested by MTT reduction assay against two mouse tumor cell lines:melanoma B16 and fibrosarcoma L929.They were also tested for cytotoxicity against normal mouse peritoneal macrophages.The proliferation inhibitory effect of the complexes compared to that of the ligand proved their cytotoxic/cytostatic properties against both the tumor cell lines.In addition,the complexes were less cytotoxic against normal mouse macrophages and were able to modulate NO release by activated macrophages.The obtained results were in accordance with our previously published data concerning the activity of lanthanide(Ⅲ) complexes with other coumarin derivatives.  相似文献   

8.
A novel coordination polymer,[Pr2(BIPA)3(H2O)2].2H2O(1)(H2BIPA=5-bromoisophthalic acid),was prepared by hydrothermal synthesis and characterized by IR spectroscopy,elemental analysis and single-crystal X-ray diffraction.The crystal was of monoclinic system,space group C2/c,with a=1.98037(14),b=1.44189(14),c=2.15281(18) nm,β=95.220(2)°,V=6.1218(9) nm3,C24H17Br3O16Pr2,Mr=1082.93,Dc= 2.350 g/cm3,F(000)=4096,μ=7.136 mm-1 and Z=8.The final R1=0.0608 and wR2=0.1371 for 5624 observed reflections(I>2σ(I)).Complex 1 featured an interesting 2D layer containing {Pr2(CO2)3}n right-handed and left-handed helical chains.Furthermore,hydrogen bonds linked the adjacent 2D layers to form a 3D supramolecular framework.Moreover,the near-infrared luminescent properties of 1 were also investigated in the solid state.  相似文献   

9.
Solid-liquid extraction of gadolinium was investigated from phosphoric acid medium using commercial amino phosphonic acid resin, Tulsion CH-93. The experimental conditions studied included equilibration time, acid concentration, mass of the resin, metal concentra-tion, loading and elution. The percent extraction of Gd(Ⅲ) was studied as a function of phosphoric acid (0.05-3 mol/L) using Tulsion CH-93 resin. The corresponding lgD vs. equilibrium pH plot gave straight line with a slope of 1.8. The percent extraction decreased with acid con-centration increasing, conforming ion exchange mechanism. Under observed experimental conditions the loading capacity of Tulsion CH-93 for gadolinium was 10.6 mg/g. Among several eluants screened, the quantitative elution of Gd(Ⅲ) from loaded Tulsion CH-93 was obtained with ammonium oxalate (0.15 mol/L). The extraction behavior of commonly associated metals with gadolinium was studied as a function of phosphoric acid concentration. Tulsion CH-93 resin showed selective extraction towards heavy rare earths (Lu and Yb) which could be sepa-rated from other rare earths at 3 mol/L H3PO4, similar to wet phosphoric acid (3-5 mol/L). On the other hand Gd(Ⅲ) and other rare earths were studied with chelating resin Tulsion CH-90. Light rare earths were highly extracted and these could be separated from heavy rare earths and Gd.)  相似文献   

10.
Theformationandresorptionofboneismain tainedbytheinteractionsofosteoblasts(OBs)withos teoclasts(OCs),andafunctionalimbalancebetween themmaycausethelossofbonemass.OCsaremulti nucleatedcellsformedbythefusionofmononuclear progenitorsofthemonocyte macrophagef…  相似文献   

11.
Europiumis one of the most important rare earth(RE) element .It is widely used as a component ofcathode ray tubes , with screen coated with red phos-phor ,as phosphorescent pigments ,andinlaser optics .It can also be used as neutron-absorbing material .In…  相似文献   

12.
The new lanthanum (Ⅲ) and praseodymium (Ⅲ) complexes of the general formula [Ln(L)3] (Ln=La(Ⅲ) or Pr(Ⅲ); LK=potassium salt of dithiocarbazinates) were prepared by both, conventional thermal and by the use of microwave technology. Elemental analyses, elec-trical conductance, magnetic moment and electronic, infrared, far-infrared, 1H and 13C NMR spectral studies were used to characterize the complexes. The molecular weights of few complexes were determined by FAB-mass spectra. Nephelauxetic ratio, covalency parameter and bonding parameter for these complexes were also calculated. The probable structures of the complexes were proposed. The antifungal and antibacterial activities of the complexes were evaluated. The activities were correlated with the structures of the compounds.  相似文献   

13.
S.  R.  Sabale  D.  V.  Jadhav  B.  S.  Mohite 《中国稀土学报(英文版)》2009,27(5):825-829
The sorption study of La(Ⅲ) was carried out on poly[dibenzo-18-crown-6] and L-valine medium. The quantitative adsorption of La(Ⅲ) was found at 1x10-2 to 1x10-5 mol/L L-valine. The various eluting agents were found efficient eluents for La(Ⅲ). The capacity of crown polymer for La(Ⅲ) was found to be 0.43 ±0.01 mmol/g. The tolerance limit of various cations and anions for La(Ⅲ) was determined.La(Ⅲ) was quantitatively separated from other metal ions in binary as well as multicomponont mixtures. The study was extended to sequen-tial separation of La(Ⅲ), U(Ⅵ) and Th(Ⅳ). The good separation yields were obtained and had good reproducibility (±2%). The method in-corporated the determination of La(Ⅲ) in real sample. The method was simple, rapid and selective.  相似文献   

14.
Recently ,therehasbeenconsiderablein terestinlanthanide(Ⅲ )hexacyanoferratesandtheanalogouscobalt(Ⅲ )aswellaschromium(Ⅲ )complexesbecauseoftheirpotentialascatalytic ,semiconductive ,andmagneticmate rials[1~ 4] .Forexample ,magneticstudiesonaseriesofthree dimensio…  相似文献   

15.
Syntheses aod Crystal Structures of Rare Earth Complexes with Adamantanecarboxylic Acid, [LnL_3(HL)(H_2O)]_2·2EtOH·2H_2O (Ln=Nd (1), La (2))  相似文献   

16.
New steroid dimer,ethylene bridged bis-carbamate(3) was synthesized from cholic acid in few steps. Complexes of 3 with lanthanum(Ⅲ) and calcium(Ⅱ) nitrates were prepared in reaction of 3 and appropriate metal salts. They were characterized by spectral data(Infrared(IR) ,ultraviolet-visible(UV/Vis) ,nuclear magnetic resonance(NMR) spectroscopy and fast-atom bombardment(FAB) ,electrospray(ESI) and matrix-assisted laser desorption/ionization mass spectrometry(MALDI-MS)) and elemental analysis. The similarity in complexing behavior of steroidal dimer toward calcium and lanthanum ions was observed.  相似文献   

17.
Photoluminescenceofrareearthcomplexesisin nerf-ftransitionsofthecentralions,whichhasgood monochromaticity.Rareearthionsareeasytoreact withcarboxylicacidstoformstablecomplexes,and manykindsofaromaticacidscanenhancethefluores centluminance.Considerableeffor…  相似文献   

18.
1 Phenyl 3 methyl 4 acylpyrazol 5 onederivativesarewellknownasβ diketonetypechelatingligandscoordinatingtoametalionwithoxygenatomsas“hard”Lewisbases .Dongetal .[1 ] andYangetal .[2 ] weresynthe sizedaspecialfamilyofbis( 4 acylpyrazol 5 one)derivatives ,inwhich ,two 1 …  相似文献   

19.
Reactions between the 1,3-bis(6-methylpyridin-2-yl) pyridine ligand L,C17H15N3 and LnIII(1a,1b,1c,1d) or a mixture of LnIII and CuII nitrates(2a,2b,2c,2d) resulted in a series of respectively novel mono-and heterodinuclea r complexes,where LnIII=Sm(a) ,Eu(b) ,Tb(c) ,Dy(d) . The compounds were char acterized by elemental analysis,ESI-MS and IR spectra,furthermore we obtained crystals of [H2L][Eu(NO3) 5](1b) and [CuL2][Eu(NO3) 5](2b) suitable for XRD char acterization. In the crystal structures the Eu ions are 10-coordinated with quit e a narrow range of Eu-O distances which are between 0.2436 and 0.2556 nm. In 1b the ligand molecule is protonated in both terminal rings,and the N-H groups ar e involved in the N-H…O hydrogen bonds with the same oxygen atom of one of the nitro groups. These hydrogen bonds connect the ions in 1b into the complex which is the principal building block of the structure. In 2b the [CuL2]2+ counterion s are present;the Cu is octahedrally coordinated by all nitrogen iatoms of two L molecules which are therefore almost perpendicular to each other. The electros tatic interactions between the charged species are in both cases the main drivin g force of the crystal packing.  相似文献   

20.
The water repellence and mechanical properties of the gelatin/Ce(Ⅲ) fiber(GCe fiber) were improved by heat treatment,which was an easy and non-toxic method.The microscopic morphology,mechanical properties,antibacterial activity,and cell culture of the GCe fibers by heat treatment(HGCe fiber) were investigated.It was found that the water repellence and mechanical properties of the HGCe fibers increased significantly along with temperature increase.SEM observation showed that HGCe fibers had a fairly smooth surface and a compact structure.Detailed characterization revealed that the HGCe fibers exhibited similar antibacterial activity with the GCe fibers against Staphylococcus aureus.In addition,the results of cell culture by morphological assessment and methylthiazolyl tetrazolium assay(MTT assay) indicated the good biocompatibility of GCe fibers.Therefore,the HGCe fibers could be a promising candidate biomaterial for biomedicine applications.  相似文献   

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