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1.
D152树脂对铜(Ⅱ)的吸附性能   总被引:1,自引:0,他引:1  
The sorption behavior and mechanism of D152 resin for Cu~(2+) is investigated.D152 resin has a good adsorptivity for Cu~(2+) in the HAc-NaAc medium at pH=4.73.The statically saturated sorption capacity is 309mg/g·(resin).Cu~(2+)adsorbed on D152 resin can be eluted quantitatively by using 0.1-2.0mol/L hydrochloric acid as an eluant.The apparent rate constant and activation energy are k_(298)=1.86×10~(-5) sec~(-1) and Ea=12.3kJ/mol.The sorption behavior of D152 resin for Cu~(2+) obeys the Freundlich isotherm.The sorption thermodynamic parameters of D152 resin for Cu~(2+)are enthalpy change ΔH=14.6 kJ/mol,free energy change ΔG=-0.72kJ/mol,entropy change ΔS=51.4J/(mol·K).respectively.  相似文献   

2.
In this paper, the ion transfer process of bromocresol purple(BCP) across the liquid/liquid interface has been described. The effects of the supporting eletrolyte in two phases and solvent on the transfer behavior of bromocresol purple have been investigated in detail and the relationship between the ion transfer and concentration of electrolytes in the organic phase is explained in terms of the dissociation of TBA~+ anti TPB~- in the organic phase. The proposed transfer mechanism for BCP has been proved to be reasonable by UV-spectroscopy of the products of the electrolysis in aqueous phase. The standard potential differences △_0~wφ~0 and standard Gibbs energies △_0~WG~0 of BCP transfer from water to some organic solvents are calculated. The dissociation constants of BCP obtained are in agreement with the literature values.  相似文献   

3.
The sorption behavior and mechanism of a novel chelate resin, diglycolamidic acid resin (DAAR), for Sm(lll) were investigated. The optimal sorption condition of DAAR for Sm(lll) is pH=6.0 in HAc-NaAc medium. The statically saturated sorption capacity is 190mg/g resin at 298K. The Sm(lll) adsorbed on DAAR can be eluted reaching 100% by 0.5-2.0mol/L HCI used as eluant. The resin can be regenerated and reused without apparent decrease of sorption capacity. The apparent sorption rate constant is k298= 1.96×10^-5s^-1. The apparent activation energy is 26kJ/mol. The sorption behavior of DAAR for Sm(lll) obeys the Freundlich isotherm. The thermodynamic sorption parameters, enthalpy change ΔH of DAAR for Sm(lll) is 16.9Kl/mol. The molar coordination ratio of the functional group of DAAR to Sin (111) is 3. The sorption mechanism of DAAR for Sm(lll) was examined by using chemical method and IR spectrometry. The coordination bond was formed between oxygen atoms in the functional group of DAAR and Sin(Ill).  相似文献   

4.
An ab initio molecular orbital study was performed to determine the effects of anions and cations on the π-complexation of C2H4 on MX(M=Ag, Cu; X=F, Cl). The calculated results show the following order of adsorption strength: F->Cl- for anions; Cu >Ag for cations. The results can be explained by the detailed analysis of atomic charge, orbital energy and orbital population by using the natural bond orbital(NBO) theory: (1) anions with stronger electronegativity can attract more electrons from the s orbital of M, while at the same time it does not obviously weaken the d orbital occupation of M, thus the nearly vacant s orbital and the sufficiently filled d orbitals of M help with forming σ-donation and d-π* backdonation with the π orbital and the π* orbital of olefin, respectively; (2) a smaller energy gap of symmetry-adapted orbitals between olefin and a cation can favor the electron transfer, that is why Cu forms stronger adsorption with olefin than Ag does.  相似文献   

5.
The influence of ionic surfactants,cetyltrimethylammonium bromide(CTAB),self-assembled within silica-nanochannels of a hybrid mesoporous silica membrane(HMSM) on simple ion transfer(IT)behaviors at the meso-water/1,2-dichloroethane(W/DCE) interface arrays supported by such a HMSM was investigated by voltammetry for the first time.Significantly,it is found that the CTAB in HMSM can dramatically enhance the peak-current responses corresponding to ITs of some anions and even lower their Gibbs transfer energies from W to DCE,which could be ascribed to an anion-exchange process between anions and the bromide of CTAB associated with partial ion-dehydration induced by the CTAB.This work will provide a new strategy to study anion transfer processes and improve the electroanalytical performance for anion detection at the liquid/liquid interface.  相似文献   

6.
舒庆  杨伯伦  王福安 《结构化学》2005,24(9):1083-1087
1 INTRODUCTION As a new generation of solvent and catalyst, ionic liquid has captured intensive attention in the field of green chemistry[1, 2]. The most significant physical character is that its property can be changed with different choices of anions, cations and substituents. For example, the water solubility can be altered by choosing proper substituent on cation, and decreased by increasing the length of alkyl chain. On the other hand, critical change of its physical properties can …  相似文献   

7.
自溶液中的吸附 VII: 硅胶自环己烷中吸附醇,酮和酯   总被引:3,自引:0,他引:3  
赵振国  顾惕人 《化学学报》1983,41(12):1091-1099
The adsorption isotherms of some monofunctional alcohols, ketones and esters from cyclohexane onto silica gel have been determined at 30`C and 10`C. The silica gel used bad a BET area of 417 m2/g and an average pore radius of 45A. The concentrations of free and associated hydroxyls on the silica gel were 1.4 and 4.1/100A^2 respectively. The adsorption order is cyclohexanol>n-octyl alcohol>cyclohexanone>methyl isobutyl ketone>n-propyl acetate=n-amyl acetate. The adsorption decreases with increasing temperature as normal. Except at very low concentrations, the isotherms can be represented by the Langmuir equation. The limiting adsorption, nms, on the silica gel does not accord with the stoichiometric ratio (1:1) between the free surface hydroxyl groups of the adsorbent and the adsorbate. In addition to surface conditions and the functional group of the adsorbate, it seems that the limiting adsorption is also controlled by the other factors, including temperature, solvent, and, sometimes the chain length of the adsorbate. The standard free energy (ΔG0) and standard enthalpy (ΔH0) of the adsorbates in adsorptien processes have been determined from the Langmuir parameters. The results indicate that the absolute value of ΔH0 is higher than that of ΔG0 (in other words, standard entropy ΔS0 is negative), as in the case of the adsorption of gases. Since there is practically no difference in ΔG0 or ΔH0 of adsorption between alcohols or esters, it is suggested that in dilute solution only the polar groups take part in adsorption, and the hydrocarben chains remain in solution during the adsorption process. For ketones, the absolute values of ΔG0 and ΔH0 are somewhat lower for methyl isobutyl ketone than that for cyclohexanone. A possible explanation is that in the adsorbed state the isobutyl chain of the methyl isobutyl ketone may somewhat close to the surface and thus decreases the adsorption and changes the ΔG0 and ΔH0.  相似文献   

8.
Sm(Ⅲ) was quantitatively adsorbed by amino methylene phosphonic acid resin(APAR) in the medium of pH=5.0,The statically saturated sorption capacity is 251mg/g.resin.Sm(Ⅲ) adsorbed on APAR can be reductively eluted by 2.0mol/L HCl.The sorption rate constant is k298=1.35×10^-5s^-1.The sorption behavior of APAR for Sm(Ⅲ) obeys the Freundlich isotherm.The enthalpy change ΔH° of sorption is 24.9kJ/mol.The apparent activation energy is Ea=11.7kJ/mol.The sorption mechanism shows that the nitrogen and oxygen atoms of the functional group of APAR coordinated with Sm(Ⅲ) to form coordination bond.  相似文献   

9.
In this study,the electrochemiluminescent(ECL) behavior of Nickel(Ⅱ) tetrasulfophthalocyanine(NiTSPc)/H2O2 on a heated indium tin oxide(ITO) electrode was investigated.The effect of pH value,electrochemical scan mode,concentration of NiTSPc and electrode surface temperature on the ECL intensities had been studied in detail.Based on the fact that the ECL of NiTSPc can be greatly enhanced by hydrogen peroxide at the ITO electrode,a new ECL biosensor for hydrogen peroxide has been developed.The possible mechanism for the ECL of NiTSPc has also been proposed.  相似文献   

10.
Introduction The design of new solid-state sensor materials that can selectively adsorb volatile organic compounds (VOC) and produce measurable color and/or lumines-cence changes is of potential significance in the sense of environmental and public safety control.1-5 The use of metal complexes as optical sensors for VOC detection has been reported, and most of them are based on the susceptibility of metal-to-ligand charge transfer (MLCT) and/or metal-metal-to-ligand charge transfer (MMLC…  相似文献   

11.
Lithium heteropoly blue(Li5PW10^ⅥW2^ⅤO40)was used as a non-aqueous electrolyte in the polyacenic semiconductor(PAS)-Li secondary battery instead of LiClO4.The properties of the PAS-Li secondary battery,especially the effect of Li5PW10ⅥW2^ⅤO40 on the capacity,the cycle property and the self-discharging of the battery have been investigated.The results indicate that not only i5PW10ⅥW2^ⅤO40 can overcome the disadvantages of LiClO4,which is apt to explode when heated or rammed.but also the PAS-Li secondary battery assembled with the novel electrolyte has a larger capacity and smaller self-discharging than that assembled with LiClO4.Therefore,it is believed that lithium heteropoly blue is a better and novel electrolyte for the PAS secondary battery and exhibity significant and practical application.  相似文献   

12.
龚文朋  陈丹  杨水金 《应用化学》2017,34(11):1321-1328
以2-氨基对苯二甲酸、4,4'-联吡啶配体和硝酸铜为原料,在溶剂热的条件下,合成了一种的阴离子型三维金属有机框架(MOF)材料Cu(BDC-NH_2)(4,4'-Bipy)_(0.5)(BDC=对苯二甲酸根,Bipy=联吡啶)。通过IR、XRD、SEM、TG、N_2吸附法测比表面积等技术手段表征材料的结构和性能。研究了Cu(BDC-NH_2)(4,4'-Bipy)_(0.5)材料对甲基紫的吸附性能,探讨了甲基紫溶液的初始p H值和初始浓度以及不同吸附温度对吸附量的影响。结果表明,等温吸附模型符合Langmuir等温吸附模型,动力学符合拟二级动力学。热力学参数ΔG0、ΔΗ0和ΔS0,表明Cu(BDC-NH_2)(4,4'-Bipy)_(0.5)对甲基紫的吸附是自发和放热的,在溶液p H=9,温度为20℃条件下,Cu(BDC-NH_2)(4,4'-Bipy)_(0.5)对甲基紫的吸附量为60.09 mg/g,说明Cu(BDC)(4,4'-Bipy)_(0.5)材料可以通过氨基改性,提高其对染料的吸附能力。  相似文献   

13.
王军  杨许召  武金超  宋浩  邹文苑 《色谱》2015,33(12):1301-1306
在343.15~363.15 K下采用反气相色谱法对实验室合成的3种非对称双阳离子型离子液体[PyC5Pi]NTf2]2、[MpC5Pi]NTf2]2和[PyC6Pi]NTf2]2的溶解度参数进行了测定。以正辛烷、正癸烷、正十二烷、正十四烷和正十六烷作为探针溶剂,计算了在不同温度下探针溶剂在3种离子液体中的特性保留体积(Vg0)、摩尔吸收焓(ΔH1S)、无限稀释摩尔混合焓(ΔHl)、摩尔蒸发焓(ΔHv)、无限稀释活度系数(Ω1)以及探针溶剂与3种离子液体的Flory-HuggirIs相互作用参数(χ12),得到了室温下3种离子液体的溶解度参数(δ2)为28.52~32.66 (J·cm-3)1/2。分子结构中含有4-甲基吗啉比含有吡啶时溶解度参数更大。随着两个阳离子间连接基碳数的增加,溶解度参数增大。这一结果对研究离子液体的溶液性质和应用有指导作用。  相似文献   

14.
A novel energetic combustion catalyst, 4-amino-3,S-dinitropyrazole copper salt ([Cu(adnp)2(H2O)2]), was synthesized in a yield of 93.6% for the first time. The single crystal of [Cu(adnp)2(H2O)2] was determined by single crystal X-ray diffraction. It crystallizes in a triclinic system, space group p^-1 with crystal parameters a = 5.541(3) A, b = 7.926(4) A, c = 10.231(5) A,β = 101.372(8)°, V = 398.3(3) A3, Z = 1, μ = 1.467 mm^-1, F(0 0 0) = 243, and Dc = 2.000 g cm^-3. The thermal behavior and non-isothermal decomposition reaction kinetics of [Cu(adnp)2(H2O)2] were studied by means of different heating rate differential scanning calorimetry (DSC). The kinetic equation of major exothermic decomposition reaction for [Cu(adnp)2(H2O)2] was obtained. The entropy of activation (△S≠), enthalpy of activation (△H≠), free energy of activation (△G≠), the self-accelerating decomposition temperature (TSADT) and the critical temperature of thermal explosion (Tb) are 59.42 j mol^-1 K^-1, 169.5 kJ mol^-1, 1141.26 kJ mol ^-1 457.3 K and 468.1 K, respectively.  相似文献   

15.
用MP2方法得到F-(H2O)n(n=1~4)体系的优化几何结构.依据优化结构计算偶极矩μ0、极化率α0、各向异性极化率Δα和一阶超极化率β0,研究了基组效应.讨论了溶剂水分子数、溶剂水分子排布及溶剂层数变化诸因素对体系超极化率等性质的影响.  相似文献   

16.
研究了Keggin结构钼磷杂多化合物Na5[PM(H2O)Mo11O39]·nH2O(M=Mn2+,Co2+,Ni2+,Cu2+,Zn2+在溶液中的氧化还原性质,发现环境的改变可对杂多阴离子的极谱半波电位产生影响,其影响程度的大小决定于过渡金属离子本身的性质。取代后的钼磷杂多阴离子的半波电位顺序为Ni2+>Co2+>Zn2+>Cu2+>Mn2+,pH值的变化影响氧化还原性质,并阐述了变价金属Cu2+对杂多阴离子氧化还原性质的影响.  相似文献   

17.
有关 DNA与金属配合物反应机理和作用模式的探讨是生物无机化学研究的重要内容之一 .目前的研究 [1~ 4] 表明 ,有大共轭配体配位的八面体金属配合物以静电作用或插入方式与DNA结合 .外消旋 [Ni( phen) 3]2 +及其旋光异构体与 DNA作用机理的研究曾有报道 [4] .但用电化学方法研究其旋光异构体与 DNA作用则未见详细报道 .本文用电化学方法和 CD谱研究了 Δ- ,∧ - [Ni( phen) 3]2 +配合物与 DNA的作用 .两种方法所得结果均表明 Δ- ,∧ - [Ni( phen) 3]2 +与 DNA作用时 ,Δ构型配合物的插入作用比∧构型配合物的强 .该法与平衡透析…  相似文献   

18.
NENU-n系列多酸基金属有机框架杂化物(POM@MOFs)是将一系列性能优异的Keggin型杂多酸封装到Cu3(BTC)2框架中形成的, 在催化和质子传导等领域展示出优异的性能. 本文在前期工作的基础上发展了一种在铜箔上原位合成POM@MOFs的新方法, 即向反应液中通入氧气, 利用酸性条件下氧气能将Cu0氧化为Cu2+的特性为金属有机框架的生长提供铜离子源, 使氧化能力较弱的Keggin型钨系杂多酸也可在铜基底上原位合成纯相NENU-n系列杂化物. 该方法可在室温条件下进行, 简便、 快速且原子经济性高. 同时发现在不添加任何调节剂的条件下, 利用该方法能生成形貌可控的POM@MOFs, 其形貌依赖于杂多酸阴离子所带的电荷. 电荷高的杂多阴离子可以得到立方体形貌, 而电荷低的杂多阴离子得到八面体形貌. 利用合成的材料对芥子气模拟物2-氯乙基乙基硫醚(CEES)的催化氧化反应进行了研究, 结果表明暴露活性位点更多的立方体形貌的NENU-40[K5BW12O40/Cu3(BTC)2]展现出更优异的催化活性, 10 min内即可将2-氯乙基乙基硫醚完全转化为无毒的亚砜.  相似文献   

19.
由于琥珀酰胆碱离子(Sch2+)在水(w)和邻硝基苯甲醚(NA)界面的传递半积分半微分循环伏安波与常规新极谱波的特性相似,测定了Δwoφ1/2、响应斜率、n和DSchw2+.据此制备了以四苯硼琥珀酰胆碱[Sch(TPB)2]为活性材料、邻硝基苯甲醚和邻苯二甲酸二丁酯(DBPH)为混合溶剂的Sch2+-PVC液膜电极.电极特性与Sch2+离子在w/NA界面传递所预示的结果相似.试验了电极对某些离子的选择性系数和回收率.  相似文献   

20.
The crystallization of NH4NO3 under compressed Langmuir monolayers of carboxybe-taine(C22N3COO-),C22H15N(CH2)3(CH2)3COO--[C22N3COO-] and dioleoyl-L-a-lecithin(DOPC) was studied by means of π-A. ΔV-A and fluorescence microscopy (FM). The surface pressure, surface potential and molecular area of C22N3COO- were decreased on the NH4NO3 solution subphase. The surface pressure and molecular area of DOPC was increased. The surface potential of DOPC was decreased. We can directly observe the surface crystallization of NH4NO3 by FM. The results revaled that C22N3COO- monolayer was the promoter of NH4NO3 surface crystallization. In contrast,DOPC monolayer was the inhibitor of the surface crystallization of NH4NO3.  相似文献   

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