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研究了溶液中无机盐、pH值对氨基修饰超高交联大孔树脂NDA-99、氧修饰超高交联大孔树脂NDA-150和大孔树脂XAD-4吸附对硝基苯胺的影响。结果表明,无机盐对吸附影响不大;NDA-99、NDA-150在中性范围吸附量最大,XAD-4的吸附量随pH增大而增大;3种树脂的吸附等温线都能很好的利用Freundlich方程进行拟合,吸附皆为放热反应且为优惠吸附;3种树脂的饱和吸附量大小依次为NDA-150>NDA-99>XAD-4。依据上述结论,采用NDA-150处理对硝基苯胺生产母液废水,每批次处理量为40BV,废水中对硝基苯胺浓度由2130mg/L降至9.6mg/L,去除率达99.5%,吸附后的树脂采用95%的乙醇可完全再生,高浓度对硝基苯胺乙醇再生溶液经蒸馏可回收对硝基苯胺和脱附剂,实现了废水治理与资源化的统一。 相似文献
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通过静态吸附实验,研究了大孔交联聚苯乙烯树脂(XAD-4)、氧修饰超高交联聚苯乙烯树脂(NDA-100)和胺基修饰超高交联聚苯乙烯树脂(ND-90)对乙醇.水溶液中硫辛酸的吸附热力学及动力学特性,结果表明:硫辛酸在XAD-4树脂上是单层吸附,符合Langmuir等温吸附方程,吸附过程符合准一级动力学吸附方程。硫辛酸在NDA-100和ND-90树脂上的吸附也符合Langmuir等温吸附方程,但并不只是单层吸附,同时兼有毛细管凝聚和微孔填充作用,吸附过程可分为大孔和中孔区的吸附以及微孔区的吸附两个阶段,两个阶段都符合准一级动力学吸附方程。 相似文献
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大孔树脂对磺酸类化合物吸附行为的研究 总被引:9,自引:0,他引:9
用4种大孔树脂ND-022,ND-900,NDA-99和NDA-100作为吸附剂,分别对水溶液中甲基磺酸钠、苯磺酸钠、对甲基苯磺酸钠和2-萘磺酸钠等磺酸盐进行吸附.探讨了溶液的初始pH值对不同类型树脂吸附磺酸类物质的影响,并通过动态吸附实验研究了SO4^2-对树脂吸附磺酸盐的影响.实验结果表明,复合功能树脂NDA-99对磺酸类化合物具有良好的吸附性能,且其选择性优于弱碱树脂ND-900,这为进一步研究大孔树脂对磺酸类物质的吸附机理和实际工业应用提供了一定的理论依据。 相似文献
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2-噻吩乙酸在三种不同树脂上的吸附热力学和动力学研究 总被引:12,自引:0,他引:12
通过静态吸附实验,研究了XAD-4,NDA-100和ND-90吸附树脂对水溶液中2-噻吩乙酸的吸附热力学及动力学特性,结果表明,2-噻吩乙酸在XAD-4树脂上是单层吸附,符合Langmuir等温吸附方程,吸附过程符合准一级动力学吸附方程.2-噻吩乙酸在NDA-100和ND-90树脂上的吸附也能用Langmuir等温吸附方程表示,但并不只是单层吸附,而主要是由毛细管凝聚和微孔填充作用造成的吸附,吸附过程可分为大孔和中孔区的吸附以及微孔区的吸附两个阶段,两个阶段都符合准一级动力学吸附方程. 相似文献
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氯球和对甲基酚发生Friedel-Crafts反应制备对甲基酚修饰的超高交联树脂(简记为GQ-03),研究GQ-03树脂对4-硝基苯胺(PNA)的吸附性能。实验结果表明:GQ-03树脂的比表面积高达1154.45m2/g,树脂孔径分布在微孔(0~2nm)、中孔(2~50nm)区;GQ-03树脂对PNA的吸附性能优于商业NDA-88、NDA-99、NDA-150、XAD-4和H103树脂;当溶液pH值在3.1~8.0之间,GQ-03树脂对PNA的吸附量最大;GQ-03树脂对PNA的吸附量随温度的升高而降低,树脂对PNA的吸附等温线符合Freundlich模型;GQ-03树脂对PNA的饱和吸附量为154.41mg/mL,树脂可用8.8BV 80%乙醇和1mol/L HCl混合溶液解吸,解吸率为98.82%。 相似文献
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邻硝基苯甲醚生产废水预处理工艺的研究 总被引:3,自引:0,他引:3
采用"酸化-树脂吸附"法对邻硝基苯甲醚生产废水进行预处理研究。比较了XAD-4、NDA-88、NDA-99、NDA-150几种树脂对酸化后废水中邻硝基苯酚的静态吸附行为,并选用吸附量较大的NDA-150树脂对该废水进行了吸附及脱附研究。结果表明,pH为4时,NDA-150树脂的平衡吸附量4.38mmol/g。动态吸附处理量为40BV(树脂体积)时,酚去除率95%,以8%NaOH为脱附剂,温度333K,脱附率98%。该工艺CODCr总去除率92%,邻硝基苯酚总去除率99%,每升废水可回收邻硝基苯酚10.8g,纯度大于97%。 相似文献
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<正>Adsorption ofhumic,tannic and gallic acids by a macro weakly basic ion-exchange resin JN-01 was studied.The adsorption capacity of this resin for gallic and tannic acids is much higher than that for humie acid,which can be explained on the basis of both their molecular size and ionization degree.Furthermore,humic acid is separated into different components with molecular weight in the range from 2000 Da to 100000 Da by ultra-filter,and their adsorption isotherms on resin JN-01 indicate that humic acid's molecular weight is an important factor which makes significant influence on adsorption.Finally,changes in the amount of Cu~(2+) and Pb~(2+) adsorbed on resin JN-01 as a function of the concentration of each of these three acids were studied.A large increase in the heavy metal ions uptake is observed in the presence of humic substance,such advantages are due to the interactions between the heavy metal ions and the unbound functional groups of the adsorbed organic acids. 相似文献
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弱碱性大孔吸附树脂对腐殖酸的吸附 总被引:4,自引:0,他引:4
研究了腐殖酸分子量对弱碱性大孔树脂吸附腐殖酸的影响, 阐明了溶液中小分子芳环化合物(苯酚)及盐含量对树脂吸附腐殖酸的影响机制. 结果表明, 树脂对低分子量腐殖酸的吸附效果要优于高分子量腐殖酸; 低浓度苯酚在溶液中可以促进树脂吸附腐殖酸, 但溶液中苯酚浓度过高会对树脂吸附腐殖酸产生抑制作用; 溶液中的盐对树脂吸附腐殖酸的影响取决于溶液的pH值. 相似文献
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Modeling of copper(II) and lead(II) adsorption on kaolinite-based clay minerals individually and in the presence of humic acid 总被引:4,自引:0,他引:4
The aim of this study is to explain how clay minerals adsorb heavy metals individually and in the presence of humic acid, and to model heavy metal adsorption specifically based on surface-metal binary and surface-metal-ligand ternary complexation. The adsorption of Cu(II) and Pb(II) on kaolinite-based clay minerals has been modeled by the aid of the FITEQL3.2 computer program using single- and double-site binding models of the Langmuir approach. Potentiometric titrations and adsorption capacity experiments were carried out in solutions containing different concentrations of the inert electrolyte NaClO4; however, the modeling of binary and ternary surface complexation was deliberately done at high ionic strength (0.1 M electrolyte) for eliminating adsorption onto the permanent negatively charged sites of kaolinite. A "two-site, two pKa" model was adapted, and as for the two surface sites responsible for adsorption, it may be arbitrarily assigned that [triple bond]S1OH sites represent silanol and organic functional groups such as carboxyl having pKa values close to that of silanol, and [triple bond]S2OH sites represent aluminol and organic functional groups such as phenolics whose pKa values are close to that of aluminol, as all the studied clays contained organic carbon. Copper(II) showed a higher adsorption capacity and higher binding constants, while lead(II), being a softer cation (in respect to HSAB theory) preferred the softer basic sites with aluminol-phenol functional groups. Heavy metal cations are assumed to bind to the clay surface as the sole (unhydrolyzed) M(II) ion and form monodentate surface complexes. Cu(II) and Pb(II) adsorption in the presence of humic acid was modeled using a double-site binding model by the aid of FITEQL3.2, and then the whole system including binary surface-metal and surface-ligand and ternary surface-metal-ligand complexes was resolved with respect to species distributions and relevant stability constants. Electrostatic effects were accounted for using a diffuse layer model (DLM) requiring minimum number of adjustable parameters. Metal adsorption onto clay at low pH increased in the presence of humic acid, and the metal adsorption vs pH curves of metal-kaolinite-humic acid suspensions were much steeper (and distinctly S shaped) compared to the wider pH-gradient curves observed in binary clay-metal systems. The clay mineral in the presence of humic acid probably behaved more like a chelating ion-exchanger sorbent for heavy metals rather than being a simple inorganic ion exchanger. 相似文献
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Preparation, Properties and Mechanism of Inhomogeneous Calcium Alginate Ion Cross-linking Gel Microspheres 总被引:1,自引:0,他引:1
Inhomogeneous calcium alginate ion cross-linking gel microspheres,a novel ion absorbent,were prepared by dropping a sodium alginate solution to a calcium chloride solutioin via an electronic droplet generator.Calcium alginate microspheres have uniform particle sizes.a smooth surface and a microporous structure.The electrode probe reveals the inhomogeneous distribution of calcium ions with the highest concentration on the surface,and the lowest concentration in the cores of the spheres.As a novel ion adsorbent,calcium alginate gel microspheres have a lower limiting adsorption mass concentration,a higher enrichment capacity and a higher adsorption capacity for Pb^2 than usual ion exchange resins.The highest percentage of the adsorption is 99.79%.The limiting adsorption mass concentration is 0.0426mg/L.The adsorption capacity for Pb^2 is 644mg/g,Calcium alginate gel microspheres have a much faster ion exchange velocity than D418 chelating resin and D113 polyacrylate resin.The moving boundary model was employed to interpret the ion exchange kinetics process,which indicates that the ion exchange process is controlled by intraparticle diffusion of adsorbable ions.So the formation of inhomogeneous gel microspheres reduces the diffusion distance of adsorbable ions within the spheres and enhances the ion exchange velocity.Alginate has a higher selectivity for pb^2 than for Ca^2 and the selectivity coefficient KCa^Pb is 316. As an ion cross-linking gel,calcium alginate inhomogeneous microspheres can effectively adsorb heavy metal Pb^2 at a higher selectivity and a higher adsorption velocity.It is a novel and good ion adsorbent. 相似文献
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Seven different types of thio- and/or amine-modified cellulose resin materials were synthesized and their mercury (II) ion adsorption properties determined. All seven resins showed good mercury (II) adsorption capability in the more neutral pH regions. However, the o-benzenedithiol- and o-aminothiophenol-modified cellulosic resins were found to be very effective in removing mercury (II) ions from strongly acidic media. For example, 93.5-100% mercury (II) ion recoveries from very acid aqueous solutions (nitric acid concentration ranged from 0.1 to 2.0 mol/L) were obtained using the o-benzenedithiol-modified resin while recoveries ranged from ca. 50% to 60% for the o-aminothiophenol-modified resin. An adsorption capacity of 23 mg (as Hg atoms) per gram of resin was observed for the o-benzenedithiol-modified cellulose in the presence of 1.0 mol/L nitric acid. This same resin shows very good selectivity for mercury (II) as only ruthenium (II) also somewhat adsorbed onto it out of 14 other metal ions studied (Ag(+), Al(3+), As(3+), Co(2+), Cd(2+), Cr(3+), Cu(2+), Fe(3+), Mn(2+), Ni(2+), Pt(2+), Pb(2+), Ru(2+), and Zn(2+)). 相似文献
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聚(丙烯酸-co-丙烯酰胺)/蒙脱土/腐殖酸钠复合物对Pb2+的吸附性能 总被引:4,自引:1,他引:3
用制备的聚(丙烯酸-co-丙烯酰胺)/蒙脱土/腐殖酸钠复合吸附剂,研究了溶液pH值、吸附时间和Pb2+溶液初始浓度等因素对重金属Pb2+的吸附性能,探讨了复合吸附剂对Pb2+的吸附机理。结果表明,在pH值为6.0、吸附时间2 h、Pb2+溶液初始浓度0.01 mol/L和吸附剂用量0.10 g的条件下,复合吸附剂对Pb2+的吸附量达到364.05 mg/g,平衡所需的时间为15 min。与蒙脱土相比,复合吸附剂具有更高的吸附容量和更快的吸附速率。 相似文献
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《Arabian Journal of Chemistry》2019,12(8):2540-2547
The adsorption of lead onto agricultural soil in the presence of organic compounds such as, humic acid, gallic acid or phenol was studied. The study included the factors affecting the adsorption process such as contact time, pH, adsorbent dose, metal concentration and organic ligands concentration. The experimental isotherm data were found to fit both Langmuir and Freundlich isotherms. The results show that the pseudo second-order equation provides the best correlation for the adsorption process. The results indicate that both humic acid and phenol increase the adsorption of lead while gallic acid slightly decreases the adsorption. 相似文献