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1.
用羧酸处理的笼形聚偕胺肟树脂(RCO2H/ACAO)吸附Pd(Ⅱ)、Ir(Ⅳ)、Pt(Ⅳ)、Ag(Ⅰ)、Au(Ⅲ)离子的能力与羧酸性质有关,巯其乙酸/ACAO树脂对Pd(Ⅱ)、Ir(Ⅳ)和Au(Ⅲ)吸附容量较高,乙二酸/ACAO树脂则对Ag(Ⅰ)和Pt(Ⅳ)离子有稍强的吸附能力。除Pd(Ⅱ)外,RCO2H/ACAO树脂吸附贵金属离子的能力低于笼形聚偕胺肟树脂(CAO)和碱处理笼形聚偕胺肟树脂(BC  相似文献   

2.
碱处理笼形聚偕氨肟树脂(BCAO)对羧酸表现出强的吸附能力。一元羧酸在BCAO树脂上以多层吸附为主要特征。二元和三元羧酸则以单层吸附占优势。后者可能是以双阴离子的一个负极吸着在BCAO树脂表面,形成了对其他羧酸阴离子起排斥作用的负离子场。另外,双阴离子也有可能和两个氨基结合形成次级交联,妨碍着其他离子迁移和扩散。  相似文献   

3.
考查了碱处理笼形聚偕胺肟树脂和乙酸,硝酸或盐酸处理的笼形聚偕胺肟树脂对卤化物,卤酸盐和卤素的吸附行为。发现BCAO和HOAc/ACAO不吸附卤化物和卤酸盐;HNO3/ACAO和HCl/ACAO对两类化合物表现出不同吸附能力。  相似文献   

4.
笼形聚偕氨肟树脂的研究:酸处理树脂的吸附性能   总被引:5,自引:3,他引:5  
笼形聚偕氨肟树脂(CAO)经盐酸处理垢,伯胺基转变成胺盐。酸处理笼形聚偕氨肟树脂(ACAO)对Mg^2+,Ca^2+,Ba^2+,Mn^2+,Co^2+,Ni^2+离子不吸附;对Zn^2+,Cd^2+,Cu^2+,Pb^2+离子的吸附效率在20%以下,但对Hg^2+离子的吸附效率则高达71.2%;对一些金属络阴离子的吸附效率顺序是Fe(CN)^2-6>Cr2O^2-7>MoO^2-4>PtCl^2  相似文献   

5.
用表面增强拉曼散射光谱(SERS)和时间分辨SERS光谱(TRSERS)等技术首次研究了烯丙基硫脲(ATU)在HClO4、H2SO4和HNO3介质中与无机阴离子在银电极上的电化学共吸附行为.提出ATU很可能以S端与银电极表面形成化学吸附键,仲氨基相对伯氨基距离表面较近,整个分子偏向烯丙基一侧倾斜吸附在表面上.ClO-4、SO2-4和NO-3等弱吸附无机阴离子均能被ATU诱导共吸附在其质子化了的仲氨基上,这3种无机阴离子被ATU诱导共吸附的强弱顺序是ClO-4>SO2-4>NO-3.被诱导共吸附的无机阴离子对ATU在电极表面的化学吸附起到稳定剂的作用,有利于ATU在电极表面形成致密的吸附层  相似文献   

6.
笼形聚偕胺肟树脂的研究HX/ACAO树脂吸附贵金属   总被引:3,自引:0,他引:3  
氢卤酸、硝酸、硫酸、磷酸和硼酸处理的笼形聚偕胺肟树脂(HX/A-CAO)对Ag+和等贵金属离子的吸附能力按如下顺序:PdCl42-:H3BO3/ACAO>BCAO>H3PO4/ACAO>HI/ACAO>H2SO4/ACAO>HCl/ACAO>HNO3/ACAO>HF/ACAO.IrCl62-:BCAO>H3PO4/ACAO>H3BO3/ACAO>HCl/ACAO>HF/ACAO>HI/ACAO>H2SO4/ACAO≥HNO3/ACAO.PtCl62:BCAO>H3BO3/ACAO>H2SO4/ACAO>HNO3/ACAO>HCl/ACAO>HF/ACAO>H3PO4/ACAO>HI/ACAO.Ag+:BCAO>H3BO3/ACAO>HI/ACAO>H2SO4/ACAO>HF/ACAO>HCl/ACAO>H3PO4/ACAO>HNO3/ACAO.AuCl4-:BCAO>H3BO3>H3PO4/ACAO>HF/ACAO>HCl/A-CAO>H2SO4/ACAO>HI/ACAO>HNO3/A-CAO.研究了H3BO3/ACAO树脂对Ag+和离子的吸附动力学,讨论了吸附机理.  相似文献   

7.
刘育  侯瑞玲 《催化学报》1996,17(2):111-116
应用FTIR和脉冲反应技术研究了CO2和O2在Ag-Ba-Ca-K/α-Al2O3上的吸附及CO2对C2H4环氧化,完全氧化及环氧乙烷(EO)深度氧化反应的影响。研究结果表明,CO2和表面吸附氧在负载银催化剂表面存在竞争吸附,CO2对表面吸附氧有置换作用,该作用降低了银催化剂表面吸附氧的浓度,并且所形成的碳酸根物种改善了乙烯环氧化反应活性氧种的表面分布,对C2H4的环氧化反应有一定的抑制作用,但是  相似文献   

8.
碱式纤维系基磁性聚偕胺肟树脂(BMAO)吸附(NH4)IrCl6是快速过程,属超当量吸附。吸附结果生成AO-Ir和AO2-Ir3络合物,随后Ir(Ⅳ)被偕胺肟基还原为Ir(0),聚集成球状晶簇随着在树脂表面。  相似文献   

9.
碱式纤维素基磁性聚偕胺肟树脂(BMAO)吸附(NH4)2IrCl6是快速过程,属超当量吸附。吸附结果生成AO-Ir和AO2-Ir3络合物,随后Ir(Ⅳ)被偕胺肟基还原为Ir(0),聚集成球状晶簇附着在树脂表面。  相似文献   

10.
以生物碱(咖啡因)为衍生化试剂,用浸渍法使其负载于活性炭(AC)上,制成一种新的金属阴离子吸附材料———负载咖啡因-活性炭(CAC)。用ICP-AES研究了该吸附材料对金属阴离子[Mo7O24]6-的吸附性能;考察了其化学稳定性;还研究了不同浓度硫酸和氨水对待测物吸附率和解脱率的影响及共存离子的干扰影响。  相似文献   

11.
HAuCl_4在笼形聚偕胺肟树脂上的吸附及结晶过程   总被引:3,自引:0,他引:3  
制备了一系列以无机酸、有机酸和酚类化合物处理的宪形聚偕胺后树脂(HX/ACAO、RCO2H/ACAO、Ph/ACAO),测定了它们对HAuCl4的吸附容量,发现吸附能力与质子酸的pka值有关,酸阴离子的结构也有一定的影响,pka值越高,酸阴离子的空间位阻越小,吸附HAuCl4的能力越强。从扫描电镜观察到HAuCl4被还原为单质金后,在ACAO表面上形成晶核,并迅速增长成晶粒、晶须和晶块。  相似文献   

12.
测定了Ag+离子在笼形聚偕胺肟树脂(CAO)及其酸、碱处理产物(ACAO、BCAO)上的吸附容量.Ag+离子在BCAO树脂上吸附容量较高,但同非选择性吸附,在ACAO上的吸附容量则与处理树脂的酸的pKa值有关.用高pKa值的硼酸、苯酸和对氨基酚处理所得的ACAO树脂的吸附容量接近BCAO树脂的水平,认为是胶后胺肟基发生互变异构所致.吸附动力学表明Ag+离子在H3BO3/ACAO和C6H5OH/ACAO树脂上进行多层吸附.在吸附中伴随有氧化还原反应并生成Ag(O)微晶的过程.  相似文献   

13.
研究了碱式笼形聚偕胺树脂(BCAO)吸附Pd(Ⅱ)的行为.溶液pH值对吸附容量有重要的影响.在一定条件下,BCAO在中性溶液中吸附Pd(Ⅱ)的量是酸性溶液中的一倍以上,但提高溶液的酸性有利于从稀溶液中回收钯.Pd(Ⅱ)在盐酸溶液中显H_2PdCI_4结构.吸附结果生成AO-Pd络合物.当溶液被碱中和至近中性时,Pd(Ⅱ)以Pd~(2+)和[Pd(OH)_2CI_2]2-的形式存在,吸附过程中先后生成AO-Pd,AO-Pd_2和AO_2-Pd_3先等不同组成的给合物.由于AO与Pd(Ⅲ)之间较大的电位差,部分Pd(Ⅱ)被还原成Pd(0),并汇聚在BCAO表面上.  相似文献   

14.
考查了碱处理笼形聚偕胺肟树脂(BCAO)和乙酸、硝酸或盐酸处理的笼形聚偕胺肟树脂(HOAC/ACAO、HNO。/ACAO、HCI/ACAO)对卤化物、卤酸盐和卤素的吸附行为。发现BCAO和HOAC/ACAO不吸附卤化物和卤酸盐;HNO3/ACAO和HCl/ACAO对两类化合物则表现出不同的吸附能力。BCAO和ACAO均吸附溴和碘,并符合Freundlich和Langmuir等温吸附方程。研究了溴在BCAO上的吸附动力学,讨论了吸附机理。  相似文献   

15.
Summary Reversed-phase liquid-liquid chromatographic systems consisting of an aqueous mobile phase and an organic liquid stationary phase of the proton acceptor tri-n-octylphosphine oxide (TOPO) inn-decane, coated on LiChrosorb RP-8, have been studied. The solutes were hydrophilic aromatic carboxylic acids and phenol. The retention of the carboxylic acids shows a minimum at 10 mM of TOPO, whereas increasingly tailing peaks have been obtained with decreasing concentrations of TOPO. This behaviour is due to a concurrent complex formation by hydrogen bonding with TOPO in the liquid stationary phase and adsorption at the interface between the support and the liquid stationary phase. The adsorption of TOPO, ketones and aromatic acids from hexane on Li-Chrosorb RP-8 has been studied, and seems to be due to residual silanol groups. The adsorption isotherm of TOPO has been determined and can be described by a two-site Langmuir adsorption model. Non polar solutes are not adsorbed. The influence of TOPO on the retention and the peak symmetry of carboxylic acids in the liquid-liquid chromatographic system appears to be due to a competition between TOPO and the acids for the same adsorption sites. No competition was found for phenol.Presented at the 14th International Symposium on Chromatography London, September, 1982  相似文献   

16.
笼形聚氨肟树脂的研究:碱处理对吸附性能的影响   总被引:3,自引:1,他引:3  
研究碱处理的笼形聚氨肟树脂(BCAO)对二价金属离子的吸附行为。吸附结果若生成2:1配的,得Mg^2+,Ca^2+,Ba^2+,Mn^2+,Co^2+,Ni^2+,Zn^2+,Cd^2+,Pb^2+,Cu^2+离子的吸附效率分别是27.1、29.2、30.4、29.0、27.1、30.8、45.0、39.8、60.3、62.1%,Hg^2+离子的吸附效率高达105%,表明在吸附过程中同时生成2:1  相似文献   

17.
笼形聚偕氨肟树脂吸附溴和碘   总被引:3,自引:0,他引:3  
用酸、碱处理的笼形聚偕氨肟树脂(ACAO、BCAO)吸附溴和碘,发现它们的吸附能力无显著差别。吸附客量与溴和碘浓度关系符合Freundlich方程.从扫描电子显微镜观察到碘在树脂表面形成微晶.联系到溴和碘的超当量吸附现象,初步认为,它们是通过物理吸附在树脂表面富集。  相似文献   

18.
The adsorption of propionic acid and benzoic acid on anion-exchange resins was analyzed, and an adsorption equilibrium equation of carboxylic acids was proposed. The adsorption of carboxylic acids on the anion-exchange resins was considered to be the sum of the physical adsorption of the molecule and the ion-exchange adsorption of the ion, which were independent of each other. For the physical adsorption of carboxylic acids, it was conformed to the Freundlich equation. For the ion-exchange adsorption of carboxylate ions, the equilibrium equation corresponded well with the experimental results for wide ranges of concentration and pH. The equation contains a selectivity coefficient S(A)(Cl) for the chloride ion versus the carboxylate ion, which was considered essentially a constant. The influent of the bicarbonate ion from carbon dioxide in air could also be expressed by the additional equilibrium equation with the selectivity coefficient S(HCO(3))(Cl) for the chloride ion versus the bicarbonate ion. Consequently, an adsorption equilibrium equation can estimate the equilibrium adsorption amounts. Even the effect of a coexisting bicarbonate ion is inconsequential when the parameters of the Freundlich isotherm equation and the selectivity coefficients of the carboxylate ion and the bicarbonate ion in each resin are determined in advance. Copyright 2001 Academic Press.  相似文献   

19.
碱性树脂吸附有机羧酸的溶胀现象   总被引:1,自引:0,他引:1  
选用强碱性树脂(201×4),弱碱性树脂(D301G)为吸附剂,以乳酸和乙酸稀溶液为吸附分离对象,实验测定了碱性树脂对有机酸和水的组分吸附量,讨论了树脂的溶胀现象.结果表明,随吸附温度的上升,碱性树脂的溶胀程度增大;随着树脂上酸的吸附量的增大,水的组分吸附量也增大.通过对水的组分吸附量的分析,提出溶胀中存在吸水量和表面增益量两个方面的影响.以水的表面增益量为基础,讨论了强碱性树脂201×4和弱碱性树脂D301G对酸-水体系的选择分离性能.  相似文献   

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