仲碳伯胺萃淋树脂吸萃金的性能及机理

研究了仲碳伯胺（Ｎ１９２３）萃淋树脂吸萃金的机理，溶液酸效应、吸附等温线、吸附速率、盐析剂效应及柱操作条件的影响等，将该树脂用于矿样中金含量的测定，结果与７１７＾＃离子交换树脂吸附法一致，取得了较好的结果。     

Multimodal sorption of nonionic dyes with two amino groups by various polymers from water

Sorption isotherms of nonionic dyes with two amino groups (one anthraquinone dye and two azo dyes) on various polymers from water were measured at 40–90°C (Nylon-6 and cellulose film) and at 95°C (polyester microfiber). The isotherms were curved, convex to upward, in the range of low dye concentration C_s in water and almost linear in the range of medium to saturated C_s. The isotherms measured at low temperature (40°C for cellulose, 40–60°C for Nylon-6, and at 95°C for polyester) were satisfactorily described by considering three concurrent modes of sorption. They are Nernst type partitioning and bimodal Langmuir sorption (sorption by the higher affinity sites with a small saturation value and that by the lower affinity sites with a large saturation value). However, for the sorption of the anthraquinone dye and one azo dye by Nylon-6 film at high temperature (80–90°C), the amount of dye sorbed by the high affinity site decreased to negligibly small. Accordingly, the isotherms were expressed well by simple dual-sorption model. © 1995 John Wiley & Sons, Inc.     

Some thermodynamic peculiarities of the nonexchange sorption of phenylalanine on dissimilar anion exchangers

It is shown that the nonexchange sorption of phenylalanine on dissimilar anion exchangers occurs by the same mechanism, determined by the structure of the amino acid, while the absorbed amount of substance depends on the sorbent structure. It is established that the micelle formation and the phenylalanineanion exchanger sorption equilibrium depend on the amount and nature of functional groups in anion exchangers. It is shown that, in the systems under investigation, the nonexchange sorption constant is determined by the constant of phenylalanine micelle formation.     

BPR树脂吸附金的性能及其分析应用研究

研究了ＢＲＰ树脂在碱性介质中对Ａｕ（Ｉ）的吸附速率，吸附容量，吸附等温线及其分析应用。     

The sorption and desorption of water in lactitols

Summary Anhydrous lactitols (A1, α- and β-lactitol), lactitol monohydrate, lactitol dihydrate and lactitol trihydrate were kept for varying times in atmospheres of different relative humidity at 20°C in equivalent size plastic desiccators. The relative humidities (8-95%) were maintained with saturated salt solutions and drying agents (silica gel and phosphorous pentoxide). The composition of the samples was monitored by thermogravimetry, differential scanning calorimetry and X-ray powder diffraction. According to these measurements both lactitol monohydrate and lactitol dihydrate were substantially stable under the conditions used. Lactitol monohydrate converts to lactitol dihydrate at the highest relative humidity used. All phases of anhydrous lactitol convert into a form of lactitol monohydrate but not to lactitol dihydrate, even at the highest relative humidity used. At a high relative humidity lactitol trihydrate easily loses part of its crystal water and converts partly to lactitol dihydrate. At a lower relative humidity, the phase forming from trihydrate is difficult to identify.     

New metal-organic frameworks with large cavities: selective sorption and desorption of solvent molecules

Five novel transition metal complexes [Cd(II) (3)(tpba-2)(2)(SCN)(6)].6 THF.3 H(2)O (1), [Cu(II) (3)(tpba-2)(2)(SCN)(6)].6 THF.3 H(2)O (2), [Ni(II) (3)(tpba-2)(2)(SCN)(6)].6 THF.3 H(2)O (3), [Cd(II) (2)(tpba-2)(SCN)(3)]ClO(4) (4), [Cu(I) (3)(SCN)(6)(H(3)tpba-2)] (5) [TPBA-2 = N',N',N'-tris(pyrid-2-ylmethyl)-1,3,5-benzenetricarboxamide, THF=tetrahydrofuran] were obtained by reactions of the corresponding transition metal salts with TPBA-2 ligand in the presence of NH(4)SCN using layering or solvothermal method, respectively. The results of X-ray crystallographic analysis showed that complexes 1, 2 and 3 are isostructural and have the same 2D honeycomb network structure with Kagomé lattice, in which all the M(II) (M = Cd, Cu, Ni) atoms are six-coordinated, and the TPBA-2 ligands adopt cis,cis,cis conformation while the thiocyanate anions act as terminal ligands. Capsule-like motifs are found in 1, 2 and 3, in which six THF molecules are hosted, and the results of XPRD and solid-state (13)C NMR spectral measurements showed that the compound 1 can selectively desorb and adsorb THF molecules occurring along with the re-establishment of its crystallinity. In contrast to 1, 2 and 3, complex 4 has different 2D network structure, resulting from TPBA-2 ligands with cis,trans,trans conformation, thiocyanate anions serving as end-to-end bridging ligands, and the incomplete replacement of perchlorate anions, which further link the 2D layers into 3D framework by the hydrogen bonds. In complex 5, the Cu(II) atoms are reduced to Cu(I) during the process of solvothermal reaction, and the Cu(I) atoms are connected by thiocyanate anions to form a 3D porous framework, in which the protonated TPBA-2 ligands are hosted in the cavities as templates.     

pH、富里酸和温度对铀酰在ZrP_2O_7上的吸附影响

采用质量滴定法和静态法分别研究了ZrP2O7的零电荷点(pHPZC)和铀酰离子在ZrP2O7上的吸附及解吸行为.铀酰离子在ZrP2O7上的吸附受体系pH、固液比、电解质种类及富里酸(FA)强烈影响,离子强度对铀酰离子在ZrP2O7上吸附的影响较小;随着固液比(m/V)和pH增大,吸附边界向左偏移;磷酸根与硫酸根对吸附有相反的影响;在低pH下,富里酸(FA)促进铀酰离子在ZrP2O7上吸附;柠檬酸根对吸附有非常大的影响;温度升高有利于吸附.采用Langmuir和Freundlich模型对吸附等温线进行拟合研究,表明Freundlich模型可以更好地拟合铀酰离子在ZrP2O7上的吸附.通过对热力学数据如(△H0,△S0和△G0)的计算可知吸附过程是自发和吸热过程.铀酰离子在ZrP2O7上吸附为不可逆吸附.     

N12胺萃淋树脂吸萃金的性能及机理研究

本文研究了Ｎ１２胺萃淋树脂在酸性介质中吸萃金的性能及不同因素对其静态分配比的影响，通过多种方法确定基萃合物的组成为ＲＮＨ＾＋３．ＡｕＣｌ＾－４并用等摩尔系列法和红外光谱探讨了该萃淋树脂吸萃金的机理。     

电化学阻抗法研究降低环氧涂层的吸水性能

降低固化环氧树脂吸水性能是提高其可靠性与寿命的重要前提之一。作者曾将常用的线型酚醛树脂(NOV)中吸水性较强的羟基用乙酸基取代,制成乙酸线型酚醛酯树脂(NOVA),并作为邻甲酚环氧树脂(ECN)的新型固化剂。用称重法研究,发现采用NOVA代替NOV所得的新型固化环氧树脂样片的饱和吸水率(M~∞)可降低一半以上。由于环氧涂层一般很薄,难以称重法研究其吸水性能,本文改用电化学阻抗法研究上述新型环氧涂层的吸水性能所得的一些有兴趣的结果,并作出了初步的解释。     

Protonation and ion exchange equilibria of weak base anion-exchange resins

Protonation and ion exchange equilibria of weak base anion-exchange resins, in which tertiary amine moieties were introduced as a functional group, were investigated by applying NMR spectroscopy to species adsorbed into the resins. ³¹P NMR signals of the phosphinate ion in the resin phases shifted to a lower field due to the influence of protonation of the tertiary amine groups of the resins in the pH range of 4-10. Protonation constants of the tertiary amine groups in styrene-divinylbenzene (DVB)-based resins were estimated to be K_H = 10^6.4 for Amberlite IRA96 and 10^6.5 for DIAION WA30 by the ³¹P NMR method using the phosphinate ion as a probe species. In addition to the low field shift caused by the protonation of the tertiary amine moieties, another low field shift was observed for the phosphinate ion in acrylic acid-DVB-based resins at a rather high pH. This shift should be due to an unexpected deprotonation in the acrylic resin: a tautomerism accompanying the proton release from the amide form to the imide one in the functional group, thus, the resin could exhibit a cation exchange property at the high pH. Protonation constants of the tertiary amine moieties in the acrylic resins were estimated to be 10^8.8 for DIAION WA10, 10^9.0 for Amberlite IRA67 and 10^9.3 for Bio-Rad AG 4-X4 on the basis of the Henderson-Hasselbalch equation using the resin phase pH estimated by the ¹³³Cs and ¹H NMR signal intensities.     

Effects of substituent groups of polyimides on sorption and diffusion of gases

Sorption rate curves of CO₂, N₂, and He gases below 1 atm were measured for polyimide films prepared from benzophenone tetracarboxylic dianhydride (BTDA) with 3,5-diaminotoluene trifluoride (DATF), 2,4-diaminotoluene (DAT), m-phenylenediamine (MPD), and diaminobenzoic acid (DABA). The molecular structures of these four polyimides differ only in the substituent groups of the diamine structure. These polyimides exhibit dualmode type sorption isotherms for carbon dioxide that are concave to the pressure axis, typical of glassy polymer/gas system. The apparent diffusion coefficients below 1 atm pressure of carbon dioxide for this series of compounds decrease in the order: BTDA-DATF > BTDA-DAT > BTDA-MPD > BTDA-DABA. A linear relation between the logarithm of the apparent diffusion coefficient and the reciprocal of free volume, calculated by the method of Bondi using density data, is found for these polyimides. However, this tendency is not observed for the other two gases. The activation energies of the apparent diffusion coefficients at 20 cmHg pressure of carbon dioxide increase with increasing cohesive energy density of the polyimides. The energy per mole of free volume elements in a liquidlike structure in each cohesive energy density may be equated to the activation energy and used to calculate the free volume. The values from the activation energy are almost the same as those from Bondi's method.     

聚氯乙烯-尼龙6树脂分离富集-分光光度法测定痕量金

本文采用聚氯乙烯－尼龙6树脂分离富集溶解于王水中的样品中的痕量金，然后用亚硫酸钠和碘化钾的混合溶液洗脱，并用硫代米酮显色。方法的检测限为1．2×10－9g／g，样品的标准回收为97％～106／，对痕量金样品的分析结果令人满意。     

The equilibrium sorption of sulfuric acid by weakly basic polyacrylic anion exchangers synthesized on the basis of polyamines

The equilibrium ion-exchange sorption of sulfuric acid by the free base form of weakly basic polyacrylic anion exchangers with the gel (Relite MG1) and porous (Relite MG1/P) structures was studied. It was proved that the bisulfate variety of the anion exchangers did not form. Solutions of resinates were found to be nonideal. Their nonideality was analyzed in terms of the theory of exchange equilibria to suggest a model of the exchange of doubly-charged anions on fixed polyamine exchange centers of Relite MG1 and Relite MG1/P anion exchangers. The type of the ion was found to have no effect on sorption parameters.     

Ionic polymers VI. Chemical stability of strong base anion exchangers in aggressive media

The chemical stability in aggressive media of two types of strong base anion exchangers was studied. The anion exchangers were a commercial Amberlite IRA-400 with a styrene structure and an unconventional resin obtained by the quaternization of a 4-vinylpyridine: 8% divinylbenzene copolymer with methylchloride. The presence of the quaternary nitrogen atoms in or out of the aromatic ring had a great influence on the chemical stability of the ion exchangers.     

Hydroxyapatite modified with silica used for sorption of copper(II)

This paper aims to increase the sorption capacity of hydroxyapatite and to find the best apatite-based material for metal ions sorption. The sorption process of copper ions from water solutions by HAP and structurally modified HAP was carried out in this work. Structural modifications of HAP were realized in the preparation phase by an addition of sodium silica into the reaction medium. The prepared materials were characterized by physical-chemical methods: IR, electron-microscopy and X-ray diffraction. The composites characterized were tested in kinetic studies regarding ion exchange and adsorption of Cu²⁺. It was revealed that the silica content, particle size and initial copper ion concentration influence the process rate. Presented at the 8th Conference on Solid State Chemistry, Bratislava, Slovakia, 6–11 July 2008.     

含硫氮螯合树脂对金、银及某些贱金属氰化物吸附性能的研究

用ＩＣＰ－ＡＥＳ研究了含硫氮螯合树脂对碱性氰化溶液中金、银、铜、铁、锌等金属离子的吸附行为。结果表明,该树脂除定量吸附金、银的氰化物外,也吸附铜、锌、铁的氰化物;吸附在树脂上的银及其它贱金属离子可以用２％ＮａＣＮ定量解吸,用硫脲－硫酸溶液可顺利地将金从树脂上洗脱下来,由此可实现金与银等元素的分离。树脂重复使用性能良好。对该树脂吸附金属氰化物的机理进行了初步探讨。