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重金属捕集剂TBA的合成及其对含铜废水的捕集性能 总被引:1,自引:0,他引:1
以无机水合肼与二硫化碳作反应物,环己醇与丙酮的混合溶液作溶剂,合成了一种新型重金属捕集剂四硫代联氨基甲酸(TBA)。重点考察了水合肼与二硫化碳的物质的量比、混合有机溶剂的用量、混合溶剂的配比、反应温度等因素对产物得率的影响,并对产物进行IR、NMR表征。研究结果表明,水合肼与二硫化碳的物质的量比为1:1、有机溶剂(环己醇和丙酮混合物)与二硫化碳的体积比为2∶3、反应温度为30℃、反应时间为2 h时,二硫化碳的转化率最高可达92.96%。将合成的重金属捕集剂四硫代联氨基甲酸用于含铜模拟废水的处理,结果表明其对于含铜废水具有优良的捕集性能。 相似文献
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以天然高分子淀粉为原料,采用季铵型醚化剂、三聚磷酸钠及尿素对其多元修饰的方法,最终获得多种电荷分布的以淀粉为基础的重金属捕集剂。通过FTIR、固体核磁共振波谱、TGA、SEM及捕集效能评价研究了淀粉基捕集剂的微观结构、特性及捕集机理。结果表明:淀粉分子成功引入阳离子季铵基团、阴离子磷酸基团及非离子酰胺基团;相对于原淀粉,所获得的中间体及终产物比表面积不断增大,分子量依次增加,有利于对重金属离子进行捕集;0.06 g淀粉基捕集剂对质量浓度为30 mg/L混合溶液中Cu~(2+)、Pb~(2+)、Cd~(2+)、Ni~(2+)的去除率分别为97.93%、99.83%、99.80%、99.53%,均达到国家排放标准;其捕集吸附过程符合伪二级吸附模型,且由电性中和反应和微孔吸附联合共同控制。 相似文献
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天然淀粉具有低毒、易降解、可循环利用等优点,经多元修饰后,具备捕集重金属的能力。使用季铵型醚化剂,磷酸盐及尿素对淀粉分子进行多元修饰,最终获得了多种电荷分布的淀粉分子修饰产品。通过红外光谱、固体核磁共振、扫描电镜及捕集效能评价等手段研究了淀粉基捕集剂的微观结构、特性及捕集机理。结果表明:淀粉分子成功引入阳离子季铵基团、阴离子磷酸基团及非离子的酰胺基团;比表面积增大,分子量增大,有利于对重金属离子进行捕集;0.06g淀粉基捕集剂对30mg/L混合溶液中铜、铅、镉、镍离子的去除率分别为97.80%、99.83%、99.23%、99.53%,均优于国家排放标准;其捕集吸附过程符合伪二级吸附模型,且由电性中和反应和微孔吸附联合共同控制。 相似文献
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二硫代氨基甲酸改性淀粉对重金属吸附选择性的研究 总被引:6,自引:2,他引:4
以玉米淀粉为原料,合成了一种新型重金属螯合剂-二硫代氨基甲酸改性淀粉(DTCS),并研究了在单-重金属溶液和混合溶液中DTCS对金属的去除情况,及影响其螯合作用的各种因素,包括重金属种类、pH值、硬度、DTCS投加量等。结果表明:DTCS对重金属离子螯合能力由强到弱的顺序为:Cu^2+〉Pb^2+〉Cd^2+〉Zn^2+〉Ni^2+;在金属离子混合溶液中,DTCS对重金属螯合速度的顺序为Cu^2+〉Cd^2+〉Pb^2+〉Zn^2+〉Ni^2+,当DTCS过量投加时,对几种重金属都可以螯合完全并从水中去除。DTCS与重金属离子形成螯合物的红外谱图说明DTCS中与金属离子键合的是S原子,从而进一步解释了所得实验现象。 相似文献
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随着印刷线路板(Printed Circuit Board,PCB)行业的不断发展,印刷线路板废水所带来的水污染问题越来越严重。铜离子及络合铜离子是印刷线路板废水中的特征污染物。为此,迫切需要研究开发水中铜离子及络合铜离子去除技术。其中,使用重金属捕集剂与废水中铜螯合反应后沉淀是废水除铜的主要方法之一。文章介绍重金属捕集剂研究进展。 相似文献
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重金属捕集剂对废水中铅捕集效果研究 总被引:6,自引:0,他引:6
研究了几种重金属捕集剂对含铅废水的处理效果,讨论了反应时间、捕集剂加入量、pH值及多种重金属离子共存条件下各种捕集剂对铅处理效果的影响。实验结果表明,在反应时间为20min,捕集剂加入量为理论用量的1.2倍,pH值为2~6时处理效果较好,捕集效率在99%以上,且多种重金属离子共存条件下对捕集效果没有影响,处理后的废水能达到重金属国家排放标准。因此采用该方法优于传统处理方法,有很好的应用前景。 相似文献
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玉米淀粉胶粘剂的改性研究 总被引:8,自引:0,他引:8
以玉米淀粉为主要原料 ,通过预糊化、氧化、加碱糊化进行化学改性 ,并加入稳定剂可制备固含量高、贮存稳定性好 ,具有一定初粘力和透明性的改性淀粉胶粘剂。本论文主要研究了改性玉米淀粉胶粘剂的主要成分配比及工艺条件对产品性能的影响。结果表明 :淀粉氧化前是否进行预糊化处理、氧化剂的用量、体系pH值、加碱糊化时碱液用量、稳定剂的种类和用量等对改性玉米淀粉胶粘剂性能影响较大。 相似文献
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In this article, the adsorption properties of poly(acrylaminophosphonic-carboxyl-hydrazide) chelating fibers for Cu(II), Cd(II), Co(II), Mn(II), Pb(II), Zn(II), Ni(II), and Cr(III) are investigated by a batch technique. Based on the research results of binding capacity, adsorption isotherm, effect of pH value on sorption, and adsorption kinetics experiments, it is shown that the poly(acrylaminophosphonic-carboxyl-hydrazide) chelating fibers have higher binding capacities and good adsorption kinetic properties for heavy metal ions. The sorption of the metal ions on the chelating fibers is strongly dependent on the equilibrium pH value of the solution. The adsorption isotherms of Cu(II) and Cd(II) on the chelating fiber exhibit a Langmuir-type equation. The adsorbed Cu(II), Cd(II), Zn(II), and Pb(II) could be eluted by diluted nitric acid. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 7–14, 1998 相似文献
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Twenty‐six new chelating polymers containing pyridyl (Py) or bipyridyl (Bipy) units as ligating centers were synthesized by free‐radical reactions of 2‐vinylpyridine, 4‐vinylpyridine, or 4‐methyl‐4′‐vinyl‐2,2′‐bipyridine with different dimethacrylate crosslinkers and evaluated for heavy metal ion sorption from aqueous solutions. Both the Py‐ and Bipy‐containing polymers are highly selective for Cu(II) over Co(II) and Ni(II) and for Hg(II) over Cd(II). The polymeric materials with Bipy binding sites generally exhibit more efficient metal ion sorption than do the corresponding Py‐containing copolymers. The metal ion sorption capacity of the copolymer also depends on the structure of the dimethacrylate crosslinker. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 849–856, 1999 相似文献
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Woven polyacryloamidoxime cloth was prepared from the polyacrylonitrile precursor via reaction in methanolic hydroxylamine. Preparation was controllable and reproducible and the reaction conditions were optimized with respect to the time of conversion, the concentration of NH2OH⋅HCl, and the temperature of conversion. The cloth produced had a large capacity for Cu(II) and Pb(II) of 71.2 and 450 mg g7minus;1 (1.12 and 2.17 mmol g−1) respectively, and adequate physical properties suitable for rigorous use. Sorption profiles of Pb(II) and Cu(II) were similar to those of chelate ion exchange resins and fibers containing the amidoxime group. The rate of uptake of metals by the cloth was found to be dependent on the percent surface area converted to amidoxime groups, the concentration and type of metal being tested for, and the time of exposure. Anomalous kinetics of sorption for Pb(II) and Cu(II) by cloth of increasing amidoxime group content were explained by a two-part sorption mechanism. Distribution coefficients of 3.5 × 106 and 1.5 × 106 for Cu(II) and Pb(II) were observed, and the average rates of uptake for Cu(II) and Pb(II) were 600 and 200 μg g7−1 day−1 (9.4 and 0.96 μmol g7−1 day−1), respectively, from dilute solution ([Cu] = 5.9 μg L−1, [Pb] = 2.8 μg L−1). Treatment of the cloth with aqueous NaOH did not improve the capacities for Pb(II) and Cu(II). © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:1175–1192, 1997 相似文献
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