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重金属离子污染具有非降解性、持续存在和累积的性质,影响着人类的生命安全。如何从水中去除重金属离子已经成为治理水污染的核心问题之一,其方法之一就是采用改性蒙脱土进行吸附处理。本文介绍了近年来重金属离子吸附用改性蒙脱土的研究新进展,重点回顾了无机改性蒙脱土、有机改性蒙脱土和无机有机复合改性蒙脱土的改性方法及其对重金属离子的去除能力及机理。提出今后改性蒙脱土研究的主要方向是合成多功能高吸附性的蒙脱土高分子复合微球、蒙脱土高分子凝胶和滤膜材料等,为今后改性蒙脱土作为重金属离子优良吸附剂的研究有一定的指导意义。 相似文献
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Shengyang Tao Chan WangWei Ma Shuo WuChanggong Meng 《Microporous and mesoporous materials》2012,147(1):295-301
A novel magnetic microsphere with thiol-functionalized mesoporous shell was fabricated by using a colloidal chemical method and cationic surfactants (CTAB) as structure-directing agents. As a high performance adsorbent, these microspheres were examined for environmental protection applications to adsorb and remove toxic phenolic compounds and heavy metal ions, sequentially, in aqueous solution. The prepared nanocomposite microspheres were mesoporous and magnetizable, with a diameter of 350-400 nm, a high surface area of 913.14 m2/g, a pore size of 2.48 nm, and a saturation magnetization of 33.9 emu/g. These multifunctional microspheres showed excellent adsorptive capability towards toxic phenolic compounds and heavy metal ions (Hg2+, Pb2+). The cation micelle made of CTAB in the mesopores has great attractive power to phenolic compounds and the adsorption capacity was as high as 144.78 mg/g for 4-methyl-2,6-dinitrophenol. The thiol-functionalized magnetic mesoporous microsphere (TMMM) which had adsorbed phenolic compounds can further adsorb metal ions after removing CTAB. The adsorption capacity was 185.19 mg/g for Hg2+ and 114.7 mg/g for Pb2+. The TMMM can be easily removed from solution by an external magnetic field. These results suggest that this kind of nanocomposites is potentially useful materials for effectively adsorbing and removing different dangerous pollutants in aqueous solution. 相似文献
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Chelating resins are useful substances in industry because of their extraordinary adsorption properties for specific metal ions. In this study, a new type of chelating resin is synthesized simply by reaction between thiourea and formaldehyde. The synthetic conditions and the structure of the product are approached and the adsorbing capacities for 11 metal ions, adsorbing rates, and selectivities investigated. The results of the experiments show that the resin has high adsorbing capacities for Ag(I): 13.1 mmol/g, and for Au(III): 6.95 mmol/g. Adsorbing rates are close to 100% in dilute solution. Isothermal adsorbing study reveals that the adsorption is monomolecular layer adsorption process. It is hopeful for the resin to be used for concentrating and retrieving Ag(I) and Au(III) ions from their dilute solutions in industry. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 3127–3132, 2001 相似文献
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Poly(methyl methacrylate) (PMMA) microspheres carrying poly(ethylene imine) (PEI) were prepared for the removal of heavy‐metal ions (copper, cadmium, and lead) from aqueous solutions with different amounts of these ions (50–600 mg/L) and different pH values (3.0–7.0). Ester groups in the PMMA structures were converted to imine groups in a reaction with PEI as a metal‐chelating ligand in the presence of NaH. The adsorption of heavy‐metal ions on the unmodified PMMA microspheres was very low [3.6 μmol/g for Cu(II), 4.6 μmol/g for Cd(II), and 4.2 μmol/g for Pb(II)]. PEI immobilization significantly increased the heavy‐metal adsorption [0.224 mmol/g for Cu(II), 0.276 mmol/g for Cd(II), and 0.126 mmol/g for Pb(II)]. The affinity order of adsorption (in moles) was Cd(II) > Cu(II) > Pb(II). The adsorption of heavy‐metal ions increased with increasing pH and reached a plateau value around pH 5.5. Their adsorption behavior was approximately described with the Langmuir equation. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 197–205, 2001 相似文献
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将聚胺大分子聚乙烯亚胺(PEI)接枝于微米级硅胶微粒表面,制得接枝微粒PEI/SiO2,然后使氯乙酸与PEI大分子中的伯、仲胺基发生亲核取代反应,形成亚氨乙酸(IAA)型螯合吸附材料IAA-PEI/SiO2. 研究了IAA-PEI/SiO2对重金属离子的螯合吸附行为和吸附机理. 结果表明,由于亚氨乙酸基团与重金属离子之间的静电作用与配位螯合作用,IAA-PEI/SiO2对重金属离子可产生强的螯合吸附作用,对Ni2+的吸附容量可达1.4 mmol/g;吸附过程为放热过程;在可抑制重金属离子水解的pH范围内,pH值越高,吸附能力越强;IAA-PEI/SiO2对重金属离子的吸附容量顺序为Ni2+> Pb2+>Cu2+>Cd2+. 相似文献
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壳聚糖/纤维素复合微球对Cu2+的吸附 总被引:1,自引:0,他引:1
制备壳聚糖/纤维素(CS/CE)和交联壳聚糖/纤维素(ECS/CE)复合微球,用于吸附重金属离子,考察了微球对Cu2+的吸附性能。溶解性测试表明交联反应可提高微球在酸性介质中的化学稳定性。静态吸附表明,CS/CE和ECS/CE均能有效吸附Cu2+,pH 6附近吸附容量最大。吸附等温线与Langmuir和Freundlich模型均吻合,由Lang-muir模型得到的Cu2+饱和吸附容量分别为38.76 mg/g(CS/CE)和34.13 mg/g(ECS/CE)。CS/CE和ECS/CE对Cu2+的吸附初期为内扩散控制,但后期为配合反应控制。FTIR和X-射线光电子能谱(XPS)分析表明,壳聚糖中的N为Cu2+的主要吸附位,发生表面配合吸附。 相似文献
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改性泥炭对Pb2+、Ni2+、Cu2+的吸附性能研究 总被引:4,自引:0,他引:4
在静态条件下,研究了改性泥炭对重金属离子Pb2+、Ni2+、Cu2+的吸附性能,着重探讨了改性泥炭去除废水中重金属离子Pb2+、Ni2+、Cu2+的适宜条件,同时对改性泥炭的吸附及解吸再生机理进行了初步分析。结果表明:在25℃条件下,当pH值为5~7、吸附剂用量为2g/L、吸附时间为2h时,改性泥炭对Pb2+、Ni2+、Cu2+的去除率分别为98.0%、96.7%、95.5%。吸附了重金属离子的改性泥炭经酸解吸再生后,可循环使用,不会带来二次污染。 相似文献
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Chelating resins have some good adsorption properties for some metal ions, especially for several noble metal ions. Thus to retrieve rare metals using chelating resins is always an interesting project for chemistry researchers. In this study we synthesized a series of chelating resins based on chitosan and investigated adsorbing capacities, adsorption rates, and adsorption selectivities for Ag(I), Au(III), Pd(II), Pt(IV), Cu(II), Hg(II), and Zn(II). The results indicate that the resins have remarkable adsorbing capacities and adsorption rates for four noble metal ions and Hg(II). For instance, one of the resins adsorbs Au(III) and the adsorbing capacity is up to 7.11 mmol/g. However, the adsorbing capacities of the resins for Cu(II) and Zn(II) are much less than for the noble metal ions. Finally, x-ray photoelectron spectroscopy studies of a chelating resin and its metal chelates were made. The result reveals that the basis of the chelations is a chemical process. © 1996 John Wiley & Sons, Inc. 相似文献
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介绍了含吡啶基吸附材料对金属离子、无机阴离子及有机污染物的吸附分离研究进展。吡啶环的氮原子具有较强的配位功能,能与多种金属离子形成络合物。这类吸附材料对金属离子显示出高的吸附容量和吸附选择性,其吸附金属离子后形成金属主体高分子,然后再利用金属离子与具有配位性能的无机阴离子、有机污染物通过路易斯酸-碱在水溶液中进行配体交换,从而达到吸附分离的目的。作为高分子交换配体(PLE),这类新型吸附材料将是今后发展的重点。 相似文献
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Kankana Baruah Riku Dutta Simanta Doley Bipul Sarma Swapan Kumar Dolui 《应用聚合物科学杂志》2024,141(2):e54767
Excess metal pollutant has affected and caused serious havoc in the lives of terrestrial as well as aquatic beings. The core of this work revolves around eradicating highly toxic heavy metal ions from underground water systems using a cost-effective, high removal efficiency polymeric adsorbent capable of adsorbing and removing ionic metals whose backbone is composed of a bio-degradable polymer, polyvinyl alcohol. The obtained adsorbent was characterized using FT-IR, HNMR, and P-XRD. Morphological studies were carried out using SEM. Detection and adsorption of metal ions were performed using SEM–EDX and AAS; wherein the adsorbent was found to remove nearly 80% of arsenic ions, 70.5% and 70.7% for lead and chromium ions while 60.7% for cadmium ions, respectively. Further, the kinetics of adsorption along with intraparticle diffusion studies were also performed to determine the mechanism alongside observing the isothermal influence of the sorbent. The adsorption capacity was seen to be highest in arsenic at around 570.42 mg g−1 thus acting as a potential and effective adsorbent for the removal of heavy metal ions from groundwater. 相似文献
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The preparation of zeolite X/chitosan (CS) hybrid microspheres for efficient removal of Cu(II) ions by an impregnation-gelation-hydrothermal synthesis technique is reported here. Characterizations by various techniques indicate that the microspheres show porous structures and intimate interaction between zeolite and CS. The adsorption experiments are performed to evaluate the adsorption capacity of zeolite X/CS hybrid microspheres and comparisons are made with binderless zeolite X microspheres, pure CS microspheres and mechanical mixed zeolite X/CS microspheres. The effects of Cu(II) solution concentration and the pH are investigated. The results indicate that zeolite X/CS hybrid microspheres with the zeolite content of 60 wt% show the highest adsorption capacity, which is 90 mg/g at the initial Cu(II) concentration of 10 mg/L and 150.4 mg/g at Cu(II) concentration of 500 mg/L. The adsorption capacity increases with increasing initial pH and reaches a maximum at pH 5.5 in the range of 0–6.0. The equilibrium adsorption data are well described by the Langmuir isotherm model, exhibiting a maximum adsorption capacity of 152.0 mg/g, and the kinetic data are well fitted with the pseudo-second-order equation. Complete removal of Cu(II) ions can be obtained even at very low concentrations. The microspheres show high adsorption capacity and efficiency for Cu(II) ions, exhibiting potential practical application in the treatment of water pollution of heavy metal ions. 相似文献
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微凝胶聚合物网络中易于引入能够与重金属离子螯合或络合的功能基团,且比表面积大,对重金属离子具有较快的吸附速率,因此,微凝胶在重金属离子的去除方面具有广阔的应用前景。本文介绍了重金属离子吸附用微凝胶研究新进展,重点回顾了基于羧基、氨基、磺酸基、羟基及巯基等多官能团化合物与重金属离子通过静电相互作用形成稳定络合物的微凝胶用于重金属离子的吸附,离子印迹型微凝胶用于重金属离子的吸附,以及基于冠醚环(苯并-18-冠-6醚)与Pb2+离子通过超分子主-客体识别作用形成稳定络合物的微凝胶用于重金属离子的吸附;描述了这三类微凝胶对重金属离子的吸附性能、优点、用途等;指出了这三类微凝胶适用于不同场合下重金属离子的吸附。 相似文献
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Poly[ethyleneglycoldimethacrylate (EGDMA)–hydroxyethylmethacrylate (HEMA)] microspheres (150–200 μm in diameter) were produced by suspension copolymerization of EGDMA and HEMA in an aqueous medium. Toluene was included in the formulations in order to produce water-swellable microspheres. Poly(vinyl alcohol) and benzoyl peroxide were used as stabilizer and initiator, respectively. Congo red was chemically attached to the microspheres as a metal chelating ligand for specific adsorption of heavy metal ions. These sorbents were characterized by an optical microscopy and a FTIR. Adsorption/desorption of cadmium (Cd2+) ions from aqueous solutions on these sorbents were investigated in batch equilibrium experiments by using an atomic absorption spectroscopy with a graphite furnace atomizer. The maximum cadmium adsorption on to the dye-attached microspheres (i.e., by complex formation) was about 18.3 mg Cd2+ ions/g polymer, which was observed at pH 6.8. While adsorption onto the plain poly(EGDMA–HEMA) microspheres (i.e., nonspecific adsorption) was about 0.93 mg Cd2+ ions/g polymer at the same conditions. More than 90% of the adsorbed cadmium was desorbed in 1 h by using 2M NaCl as an eluant. The resorption capacity of the sorbent did not significantly decrease during repeated sorption–desorption cycling. © 1996 John Wiley & Sons, Inc. 相似文献
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The adsorption properties of chitin adsorbent from mycelium of fermentation industries for the removal of heavy metal ions were studied.The result shows that the chitin adsorbent has high adsorption capacity for many heavy metal ions and Ni^2 in citric acid.The influence of pH was significant:When pH is higher than 4.0,the high adsorption capacity is obtained.otherwise H^ ion inhibits the adsorption of heavy metal ions.The comparison of the chitin adsorbent with some other commercial adsorbents was made,in which that the adsorption behavior of chitin adsorbent is close to that of commercial cation exchange adsorbents,and its cost is much lower than those commercial adsorbents. 相似文献
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水体系重金属污染治理是目前全世界所面临的一个重大挑战。传统治理方法由于成本高、效率低等问题已不符合当今社会可持续发展战略。纳米纤维素凭借其来源丰富、可再生、化学反应活性高、比表面积大、密度低等优点,在水体系重金属离子去除领域有着光明的应用前景。然而,纳米纤维素吸附材料在水体系重金属去除领域还存在吸附量较低,吸附选择性、再生性、性能稳定性较差,制备成本较高等问题,这限制了其在水体系重金属离子去除领域的工业化应用。通过改性和结构设计不断提高纳米纤维素材料的吸附效率是行之有效的途径,本文从化学改性和结构设计两方面出发,系统地综述了纳米纤维素在水体系重金属离子去除领域的研究现状,并对其中存在的科学技术问题进行总结。最后,展望了纳米纤维素在水体系重金属离子去除领域的发展趋势。 相似文献
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One of the most important properties of chitosan, a derivative of chitin, is that it is able to chelate with certain heavy metal ions, and this property can be applied to process waste water containing heavy metal ions. In this research, using BTCA/CA as a crosslinking reagent with chitosan added, cotton fabrics were cured and allowed to undergo an adsorption reaction in CuSO4 and ZnSO4 solutions. The effect of different curing temperatures and time, as well as different adsorptive temperatures and time, were studied. The cotton processed fabrics were analyzed by Fourier transform infrared analysis (FTIR), scanning electronic microscope (SEM), and thermal gravity analysis (TGA) to study the crosslinking reaction with the cotton‐processed fabrics. The results indicate: (1) the BTCA/CA‐processed cotton fabrics with an addition of chitosan have a better adsorptive capacity than the processed fabrics without chitosan; (2) the crosslinked fabrics are better in adsorbing copper ions as chitosan concentration, curing temperature and time, and adsorptive temperature and time increase; (3) the adsorption rate of copper and zinc ions are linearly proportional to the changes of time, so that the slope shows that the adsorption rate of crosslinked fabrics for copper ions is faster than for zinc ions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3264–3269, 2006 相似文献