α-酮戊二酸壳聚糖衍生物的制备及其吸附性能的研究

利用壳聚糖C2位上活泼氨基与α-酮戊二酸进行大分子反应,采用正交试验法优化合成条件,合成了带有席夫碱基团的功能高聚物（简称KCTS）。研究了KCTS对Cu(Ⅱ）、Zn(Ⅱ)、Co(Ⅱ)等重金属离子的吸附性能,对低浓度金属离子去除率分别达到100%、95.5%、43.7%,与壳聚糖、水杨醛改性壳聚糖相比,α-酮戊二酸改性壳聚糖对Cu(Ⅱ)和Zn(Ⅱ)具有良好的吸附性能,并能在Co(Ⅱ)存在下选择吸附Cu(Ⅱ）和Zn(Ⅱ）。     

Cu(Ⅱ)印迹交联壳聚糖吸附剂的制备与选择性吸附的研究

采用Cu(Ⅱ)离子为印迹离子,以壳聚糖为原料,甲醛为预交联剂,环氧氯丙烷为交联剂,通过微波法制备出改性壳聚糖吸附剂。考察了合成过程中操作条件对吸附剂吸附性能的影响。结果表明,当壳聚糖质量分数为6%、17.4 m L甲醛、8.76 m L环氧氯丙烷、酸化t为10 h、θ为70℃时,所得Cu(Ⅱ)印迹交联壳聚糖吸附剂对Cu(Ⅱ)的吸附容量高达3.466 mmol/g;在混合金属离子溶液中,该吸附剂对Cu(Ⅱ)表现出较强的吸附选择性。     

竹炭壳聚糖吸附剂的制备及对Cr(Ⅵ)的吸附性能

采用竹炭与壳聚糖复配的方法,并以海藻酸钠作为交联剂制备竹炭壳聚糖吸附剂,考察了制备过程中的交联剂种类、原料配比、操作条件及吸附过程中的吸附时间、溶液酸度等对Cr(Ⅵ)吸附性能的影响。结果表明,竹炭壳聚糖比活性炭壳聚糖具有更好的吸附性能;壳聚糖的交联剂对吸附性能的影响不大;当m(竹炭)∶m(壳聚糖)为1∶2,吸附t为30 min,溶液pH为5~7时,竹炭壳聚糖吸附剂对Cr(Ⅵ)有较好的吸附性能。     

海藻酸钠多胺微球对有机体系中Cu(Ⅱ)的去除

制备一种新型海藻酸钠多胺吸附剂,通过构建三维网状物的形式,将其制备成能吸附Cu(Ⅱ)的水凝胶微球。并探究不同的酸度、盐度、时间、有机物浓度条件下吸附剂对Cu(Ⅱ)的吸附性能。结果表明,在pH=5时,吸附剂对Cu(Ⅱ)的去除效果最好。较低浓度的磺胺甲恶唑、柠檬酸、腐殖酸会促进吸附剂对铜离子的吸附,pH=5时,促进作用最优的磺胺甲恶唑、柠檬酸及腐殖酸浓度分别为0.5,0.4,0.4 mmol/L,最大吸附量Q_e分别为0.770 8,0.711 3,0.698 8 mmol/g。     

亚氨基二乙醛肟树脂的合成及其性能的研究

介绍了苯乙烯二乙烯基苯为基体的亚氨基二乙醛肟树脂(IDAO)的合成,研究了树脂对金属离子的吸附性能,并讨论了pH对吸附的影响以及吸附的动力学效应。结果表明 IDAO 树脂对重金属离子(Cu(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Pb(Ⅱ)、Zn(Ⅱ)等),特别是高价重金属离子(Fe(Ⅲ)、Cr(Ⅳ)、V(Ⅴ))有很强的吸附作用,而对碱金属、碱土金属不吸附。     

交联壳聚糖对废水中Cu2+的吸附性能

以壳聚糖为原料制备交联壳聚糖吸附剂,并将其用于吸附废水中的Cu2+,考察了交联剂的用量、溶液中Cu2+初始浓度、pH、温度和时间等对交联壳聚糖吸附性能的影响。结果表明,壳聚糖与交联剂的用量比为m(壳聚糖)∶V(甲醛)∶V(戊二醛)=1.5g∶6mL∶4.5mL、溶液pH为6,溶液中Cu2+初始浓度为5mmol/L时吸附效果最佳,且吸附量随着温度升高而增加,吸附表现为吸热过程。     

新型合成聚合物重金属离子吸附剂及其吸附性能

阐述了新型聚合物重金属离子吸附剂的合成与改性及其对水溶液中Cd(Ⅱ)、Pb(Ⅱ)、Cu(Ⅱ)、Hg(Ⅱ)等重金属离子的吸附性能。这些聚合物重金属离子吸附剂对低浓度的重金属离子表现出了较好的吸附能力，其中聚合物吸附剂PGHyFeO—COOH对mg／L级的Pb(Ⅱ)、Cd(Ⅱ)、Hg(Ⅱ)的最大吸附量分别为211．4mg／g、155．0mg／g、147．2mg／g。这些吸附剂的吸附速度也较快，平衡吸附时间一般在60min左右，有的甚至只有几分钟。新型聚合物重金属离子吸附剂在水处理工业中具有广阔的应用前景。     

凹凸棒土/壳聚糖复合物的制备和吸附性能探究

以凹凸棒土为载体，将壳聚糖负载于凹凸棒土，得到凹凸棒土/壳聚糖(AT/CTS)改性吸附剂，用于染料废水的处理。利用紫外光谱、红外光谱和X射线衍射对AT/CTS的结构进行分析，初步探讨了AT/CTS对染料亚甲基蓝吸附性能的影响因素。结果表明：最佳吸附性能出现在吸附剂用量为10 mg、10 mL初始质量浓度70 mg·L^-1的亚甲基蓝溶液、温度30℃、pH值为13和吸附时间30 min时，此时的平均吸附率达到98.5%。同时AT/CTS吸附剂对亚甲基蓝吸附动力学符合准二级动力学模型，吸附过程符合Langmuir等温方程。     

壳聚糖固化单宁颗粒的制备及其吸附Cu~(2+)离子的研究

采用壳聚糖颗粒为固化介质,将单宁和壳聚糖以共价方式结合,制备了壳聚糖固化单宁颗粒吸附剂。采用红外光谱对所得吸附剂进行表征,并研究了各种操作条件,如溶液的pH值、溶液Cu~(2+)离子浓度、吸附时间等对吸附性能的影响。结果表明,升高溶液的pH值(实验中pH不大于7)和Cu~(2+)离子浓度会提高吸附剂的吸附量;吸附剂对Cu~(2+)离子有较快的吸附速度,60 min可达到吸附平衡;溶液中共存的Na~+离子会降低吸附剂对Cu~(2+)离子的吸附能力;对Cu~(2+)离子的吸附规律符合Langmuir吸附等温模型,最大吸附量达到75.23 mg·g~(-1)。     

壳聚糖为基质的染料亲和吸附剂对重金属离子的吸附平衡及动力学研究

以反相悬浮交联法制备了壳聚糖微球载体,并偶联染料配体(CibacronBlueF3GA),制得了新型染料亲和吸附剂。研究了吸附剂与金属离子Cu2 、Pb2 、Cd2 之间的吸附行为。结果表明,在较高的初始金属离子浓度(200￣500mg·L-1)下,金属离子在吸附剂中的平衡吸附过程较好地符合Langmiur吸附等温式,吸附剂对Cu2 、Pb2 、Cd2 的最大吸附量分别为92.12、115.40、39.78mg·g-1;吸附动力学可用拟二级速率方程来描述,计算值与实测值吻合甚好;吸附剂对各重金属离子的吸附选择性依次为:Pb2 >Cu2 >Cd2 。     

Heavy metals uptake from aqueous solutions and industrial wastewaters by humic acid-immobilized polymer/bentonite composite: Kinetics and equilibrium modeling

This study explored the feasibility of utilizing a novel adsorbent, humic acid-immobilized-amine-modified polyacrylamide/bentonite composite (HA-Am-PAA-B) for the adsorption of Cu(II), Zn(II) and Co(II) ions from aqueous solutions. The FTIR and XRD analyses were done to characterize the adsorbent material. The effects of pH, contact time, initial adsorbate concentration, ionic strength and adsorbent dose on adsorption of metal ions were investigated using batch adsorption experiments. The optimum pH for Cu(II), Zn(II) and Co(II) adsorption was observed at 5.0, 9.0 and 8.0, respectively. The mechanism for the removal of metal ions by HA-Am-PAA-B was based on ion exchange and complexation reactions. Metal removal by HA-Am-PAA-B followed a pseudo-second-order kinetics and equilibrium was achieved within 120 min. The suitability of Langmuir, Freundlich and Dubinin-Radushkevich adsorption models to the equilibrium data was investigated. The adsorption was well described by the Langmuir isotherm model. The maximum monolayer adsorption capacity was 106.2, 96.1 and 52.9 mg g^?1 for Cu(II), Zn(II) and Co(II) ions, respectively, at 30 °C. The efficiency of HA-Am-PAA-B in removing metal ions from different industry wastewaters was tested. Adsorbed metal ions were desorbed effectively (97.7 for Cu(II), 98.5 for Zn(II) and 99.2% for Co(II)) by 0.1 M HCl. The reusability of the HA-Am-PAA-B for several cycles was also demonstrated.     

Preparation of amidoximated polyester fiber and competitive adsorption of some heavy metal ions from aqueous solution onto this fiber

In this study, a fibrous adsorbent containing amidoxime groups was prepared by graft copolymerization of acrylonitrile (AN) onto poly(ethylene terephthalate) (PET) fibers using benzoyl peroxide (Bz₂O₂) as initiator in aqueous solution, and subsequent chemical modification of cyano groups by reaction with hydroxylamine hydrochloride in methanol. The grafted and modified fibers were characterized by FTIR, TGA, SEM, and XRD analysis. The crystallinity increased, but thermal stability decreased with grafting and amidoximation. The removal of Cu(II), Ni(II), Co(II), Pb(II), and Cd(II) ions from aqueous solution onto chelating fibers were studied using batch adsorption method. These properties were investigated under competitive conditions. The effects of the pH, contact time, and initial ion concentration on the removal percentage of ions were studied. The results show that the adsorption rate of metal ions followed the given order Co(II) > Pb(II) > Cd(II) > Ni(II) > Cu(II). The percentage removal of ions increased with initial ion concentration, shaking time, and pH of the medium. Total metal ion removal capacity was 49.75 mg/g fiber on amidoximated fiber. It was observed that amidoximated fibers can be regenerated by acid without losing their activity, and it is more selective for Pb(II) ions in the mixed solution of Pb‐Cu‐Ni–Co‐Cd at pH 4. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Adsorption of some heavy metal ions from aqueous solutions on Nafion 117 membrane

Nafion 117 membrane was investigated for the removal of Ni(II), Co(II), Pb(II), Cu(II) and Ag(I) metal ions from their synthesized aqueous solutions. The different variables affecting the adsorption capacity of the membrane such as contact time, initial metal ion concentration in the feed solution, pH of the sorption medium and temperature of the solution were investigated on a batch sorption basis. The affinity of Nafion 117 membrane towards heavy metal ions was found to increase in the sequence of Cu(II), Ni(II), Co(II), Pb(II), and Ag(I) with adsorption equilibrium achieved after 30 min for all metal ions. Among all parameters, pH has the most significant effect on the adsorption capacity, particularly in the range of 3.1-5.9. The variation of temperature in the range of 25-65 °C was found to have no significant effect on the adsorption capacity. Nafion 117 membrane was found to have high stability combined with repeated regeneration ability and can be suggested for effective removal of heavy metal ions such as Cu(II), Ni(II) and Co(II) from aqueous solutions.     

The adsorption behavior of Cu(II), Pb(II), and Co(II) of ethylene vinyl acetate‐clinoptilolite nanocomposites

In this study, ethylene vinyl acetate (EVA) was mixed with clinoptilolite (C), a natural zeolite, to prepare EVA‐C nanocomposites. The films were characterized by SEM‐EDS, XRD, and FT‐IR, and heavy metal removal was studied using the batch technique. The effects of the initial pH value and concentration of solutions, contact time, and filler dosage on the adsorption capacity of the composites were investigated. To study the influence of pretreatment on the filler, clinoptilolite was activated using KCl, NaCl, and HCl. Adsorption results show that equilibrium was reached after 24 h, and that sorption reached its maximum at pH values between 5 and 7. The selectivity trend was observed to be Pb > Cu > Co, which was consistent for both single and mixed metal‐ion solutions. Pretreatment significantly increased adsorption capacity of the composite, but was dependent on the conditioning reagent. Nanocomposites filled with HCl‐activated particles demonstrated a high adsorption capacity of between 70 and 80% for all three metals, while KCl‐activated particles were the least efficient with a maximum adsorption capacity of 69% for Pb(II), 54% for Cu(II) and 48% for Co(II). The adsorption data were then fitted to both Langmuir and Freundlich isotherms over the entire concentration range, and the Langmuir isotherm showed a better fit of the experimental sorption data than the Freundlich isotherm. The results obtained show that this simple methodology which can be up‐scaled has great potential for the preparation of a wide variety of similar particle‐filled adsorbent nanocomposites in other environmental remediation applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

淀粉基炭的制备及其对重金属离子的吸附性能

通过不完全炭化淀粉制备出无定形淀粉基炭材料,用X射线粉末衍射,TGA-DSC,红外光谱和比表面积测定对其进行了表征;研究了淀粉基炭对Cu2+,Pb2+,Cd2+,Zn2+的吸附性能,考察了淀粉基炭投加量、pH、温度和金属离子初始质量浓度对吸附效果的影响。金属离子的去除率随着淀粉基炭投加量的增加而上升,各种金属离子的最佳吸附pH分别为7.0(Cu2+),6.0(Pb2+),8.0(Cd2+),8.0(Zn2+)。温度越高越有利于吸附,吸附行为符合Langmuir等温吸附方程。     

Sorption studies of heavy metal ions on pectin-nano-titanium dioxide composite adsorbent

The Cu(II), Cd(II), Zn(II), and Pb(II) sorption kinetics and equilibrium on hybrid material, composed of pectin and titanium dioxide nanopowder, were examined. Parameters, such as pH and adsorbent dose, were also investigated. The experimental data were better described by the Langmuir model. The maximum adsorption capacities were 1.37, 0.68, 0.51, and 0.83 mmol/g for Cu(II), Cd(II), Zn(II), and Pb(II), respectively. The introduction of nano-TiO₂ improved the kinetics of the metal ion sorption. The titanium dioxide, despite its small content (6%), contributes to the removal of the examined metal ions and eventually to the adsorption capacity of hybrid beads.     

Facile preparation of magnetic chitosan modified with thiosemicarbazide for adsorption of copper ions from aqueous solution

In this study, magnetic chitosan modified with thiosemicarbazide (TSC‐Fe₃O₄/CTS) was facilely synthesized with glutaraldehyde as the crosslinker, and its application for removal of Cu(II) ions was investigated. The as‐prepared TSC‐Fe₃O₄/CTS was characterized by Fourier transform infrared spectroscopy (FTIR), X‐ray powder diffraction (XRD), and scanning electron microscopy (SEM). The results showed that TSC‐Fe₃O₄/CTS has high adsorption capacity and selectivity towards Cu(II) ions. Adsorption experiments were carried out with different parameters such as pH, solution temperature, contact time and initial concentration of Cu(II) ions. The adsorption process was better described by the pseudo‐second‐order model. The sorption equilibrium data was fitted well with the Langmuir isotherm model and the maximum adsorption capacity toward Cu(II) ions was 256.62 mg/g. The thermodynamic parameters indicated that the adsorption process of Cu(II) ions was exothermic spontaneous reaction. Moreover, this adsorbent showed excellent reusability and the adsorption property remained stable after five cycles. This adsorbent is believed to be one of the promising and favorable adsorbent for the removal of Cu(II) ions from aqueous solution. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44528.     

松果对废水中Cu~(2+)、Pb~(2+)、Zn~(2+)的吸附特性研究

以松果作为吸附剂进行了去除废水中Cu2+、Pb2+、Zn2+的吸附及解吸试验,研究了溶液pH值、吸附剂投加量、反应时间、溶液初始浓度对吸附效果的影响,以及不同pH值对达到吸附平衡的松果的解吸影响。结果表明:当pH值为5.0～5.5,Cu2+、Pb2+、Zn2+初始质量浓度约为25 mg/L时,吸附剂的最佳投加量分别为3、1.5、3 g/L,去除率分别为55.32%、86%、39.96%。3种重金属离子的吸附动力学方程符合Lagergren准二级动力学方程,R2均大于0.998。等温吸附研究表明:Freundlich方程能较好地描述Cu2+的等温吸附过程,Langmuir方程则能更好地描述Pb2+和Zn2+的吸附过程,用Langmuir方程拟合等温吸附数据得出松果对Cu2+、Pb2+、Zn2+的最大吸附量分别为9.10、31.65和9.60 mg/g。强酸是一种理想的Cu2+和Zn2+解吸剂。     

Preparation and characterization of an IPN type chelating resin containing amino and carboxyl groups for removal of Cu(II) from aqueous solutions

A novel IPN type chelating resin, amino-functionalized poly (glycidyl methacrylate)/poly (acrylic acid), (pGMA/pAA), was synthesized by a combination of serial reactions including, conventional radical polymerization, amination and photopolymerization. To assess the efficacy and characteristics of the resin in removal of Cu (II), batch adsorption experiments were carried out, and the effects of different parameters such as contact time, adsorbent dosage, initial metal ion concentration, temperature, and pH on the adsorption process were investigated. The results showed that 0.5 g/L dosage and pH 5 are the optimum values to achieve the maximum adsorption capacity and the adsorption kinetic of Cu (II) was well represented by pseudo-second-order kinetic model. In addition, it was found that the adsorption was mainly controlled by the film diffusion mechanism, along with a considerable contribution of the intra-particle diffusion mechanism, and Langmuir, Freundlich and Dubinin–Radushkevich (D–R) isotherm models can be used for interpreting the adsorption process. Moreover, FT-IR analysis results and the mean free energies of adsorption clearly indicate that the ion exchange and chelation mechanisms took place as dominating mechanisms simultaneously during the adsorption process. It was also found to be that IPN resin could be used at least four times without losing its original activity.     

Adsorption of Cr(III), Ni(II), Zn(II), Co(II) ions onto phenolated wood resin

In this study, phenolated wood resin was used an adsorbent for the removal of Cr(III), Ni(II), Zn(II), Co(II) ions by adsorption from aqueous solution. The adsorption of metal ions from solution was carried at different contact times, concentrations and pHs at room temperature (25°C). For individual metal ion, the amount of metal ions adsorbed per unit weight of phenolated wood resin at equilibrium time increased with increasing concentration and pH. Also, when the amounts of metal ions adsorbed are compared to each other, it was seen that this increase was order of Cr(III) > Ni(II) > Zn(II) > Co(II). This increase was order of Cr(III) > Ni(II) > Co(II) > Zn(II) for commercial phenol–formaldehyde resin. Kinetic studies showed that the adsorption process obeyed the intraparticle diffusion model. It was also determined that adsorption isotherm followed Langmuir and Freundlich models. Adsorption isotherm obtained for commercial phenol–formaldehyde resin was consistent with Freundlich model well. Adsorption capacities from Langmuir isotherm for commercial phenol–formaldehyde resin were higher than those of phenolated wood resin, in the case of individual metal ions. Original adsorption isotherm demonstrated the monolayer coverage of the surface of phenolated wood resin. Adsorption kinetic followed the intraparticle diffusion model. The positive values of ΔG° determined using the equilibrium constants showed that the adsorption was not of spontaneous nature. It was seen that values of distribution coefficient (K_D) decreasing with metal ion concentration in solution at equilibrium (C_e) indicated that the occupation of active surface sites of adsorbent increased with metal ions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2838–2846, 2006