基于高吸附大分子磁性碳基纳米复合材料的制备

发布时间：2018-03-17 12:57

本文选题：氧化石墨烯　切入点：多壁碳纳米管　出处：《济南大学》2017年硕士论文　论文类型：学位论文

【摘要】：近年来,以石墨烯(Graphene)和碳纳米管(MWCNTs)为代表的碳基材料吸附剂成为了备受关注的明星材料,主要是因为碳材料优良的化学稳定性,结构的多样性,密度低,适合大批量生产等优异的特点。但由于石墨烯自身易团聚,在水溶液中分散性较差,并且碳基材料上具有的活性吸附位点数量较少,这就限制了碳材料进一步有效的应用于污水处理。基于此,本论文首先通过改进的Hummers法制备表面含有羧基、羟基以及环氧基团的氧化石墨烯(GO);其次通过物理混杂的方法制备GO-MWCNTs杂化体,MWCNTs在GO层与层之间形成交联网络,拓宽了GO的层间距,使杂化体表面积增加;然后通过化学共沉淀法将Fe_3O_4磁性微粒沉积在GO-MWCNTs杂化体表面,合成Fe_3O_4-(GO-MWCNTs)磁性复合材料;进而采用具有丰富官能团的聚赖氨酸(PLL)、海藻酸钠(SA)及聚谷氨酸(PGA)大分子对Fe_3O_4-(GO-MWCNTs)复合材料进行表面接枝处理,得到具有丰富吸附位点,较大比表面积的磁性纳米碳基-高分子复合材料,并将这三种磁性纳米复合材料应用于污水中重金属离子及有机染料的吸附与分离。1.通过改进的Hummers法首先制备了具有单层片状结构并且表面含有有限数量的羧基、羟基、环氧基等含氧官能团的GO。X-射线衍射(XRD)与透射电镜(TEM)的表征结果,GO层状结构已分开,经计算,层间距为0.835 nm。2.通过物理混杂的方法制备GO-MWCNTs杂化体。GO与MWCNTs的最佳质量比为4:1。红外(FT-IR)与扫描电镜(SEM)的表征结果清晰说明GO与MWCNTs已有效的进行杂化。XRD测试结果表明GO-MWCNTs杂化体层间距为0.847 nm,这显然高于GO的层间距。3.通过化学共沉淀法合成Fe_3O_4-(GO-MWCNTs)磁性杂化体。Fe_3O_4与GO-MWCNTs杂化体的最佳质量比为3.2:1~3.8:1。FT-IR、SEM、热失重(TGA)测试表明Fe_3O_4已经通过Fe-O配位键分散到GO-MWCNTs杂化体表面。4.使用PLL对Fe_3O_4-(GO-MWCNTs)复合材料进行表面接枝处理,制备磁性PLL-Fe_3O_4-(GO-MWCNTs)纳米复合材料。FT-IR、TGA表征结果显示PLL已经通过酰胺键接枝到Fe_3O_4-(GO-MWCNTs)磁性杂化体表面。PLL的加入不仅大大提高了复合材料的活性吸附位点,而且提高了复合材料在水中的分散性。将该复合材料用于水溶液中阳离子染料亚甲基蓝(MB)、阴离子染料柠檬黄及重金属离子Pb(II)的吸附和分离,实验结果表明在最优吸附条件下,PLL-Fe_3O_4-(GO-MWCNTs)对MB最大吸附量计算为561.80mg·g-1,对柠檬黄最大吸附量计算为775.19 mg·g-1,对Pb(II)最大吸附量计算为1038.42mg·g-1。5.使用SA对Fe_3O_4-(GO-MWCNTs)复合材料进行表面修饰,制备磁性SA-Fe_3O_4-(GO-MWCNTs)纳米复合材料。FT-IR、TGA表征结果显示SA已经包埋Fe_3O_4-(GO-MWCNTs)磁性杂化体形成小球。将该复合小球用于MB溶液及含二价重金属离子Cu(II)、Cd(II)、Ni(II)溶液的吸附和分离实验。实验结果表明选取最优的吸附条件,该复合小球对MB的最大吸附量计算为632.91 mg·g-1,对二价重金属离子的吸附能力大小为Cu(II)Cd(II)Ni(II)。6.使用PGA对Fe_3O_4-(GO-MWCNTs)复合材料进行表面接枝处理,制备磁性PGA-Fe_3O_4-(GO-MWCNTs)纳米复合材料。FT-IR、TGA表征结果显示PGA已接枝到Fe_3O_4-(GO-MWCNTs)复合材料的表面。将该磁性复合材料用于对重金属离子Cu(II)、Cd(II)、Ni(II)的吸附和分离实验研究中。实验结果表明对重金属离子的吸附过程都遵循准二级动力学模型且吸附等温线都符合Langmuir模型,实验结果表明选取最优的吸附条件,PGA-Fe_3O_4-(GO-MWCNTs)对重金属离子的吸附能力为Cd(II)Cu(II)Ni(II)。
[Abstract]:In recent years, with graphene (Graphene) and carbon nanotubes (MWCNTs) adsorption of carbon based materials as the representative of the agent has become the concern of the star material, mainly because of the chemical stability of carbon material with excellent structure, diversity, low density, suitable for mass production and other excellent characteristics. But because graphene itself is easy reunion, poor dispersion in aqueous solution, with fewer active adsorption sites on carbon based materials and this limits the application of carbon materials further effective in sewage treatment. Based on this, this paper first through the improved Hummers method for preparing surface containing carboxyl, hydroxyl and epoxy groups of graphene oxide (GO); followed by physical method for preparation of GO-MWCNTs hybrid hybrid, MWCNTs crosslinking network is formed between the GO layer and GO layer, broaden the layer spacing, increase the surface area of the hybrid; then by chemical coprecipitation method Fe_3O_ The 4 magnetic particles deposited on the surface of GO-MWCNTs hybrid, the synthesis of Fe_3O_4- (GO-MWCNTs) magnetic composite material; then the rich functional poly lysine (PLL), sodium alginate (SA) and poly glutamic acid (PGA) molecules on Fe_3O_4- (GO-MWCNTs) composite materials for surface grafting treatment, get rich adsorption sites larger than the magnetic nano carbon based surface composite polymer materials and.1. adsorption and separation of the three kinds of magnetic nano composite materials applied in the wastewater of heavy metal ions and organic dye by the improved Hummers method is first prepared with a single sheet structure and the surface with a limited number of carboxyl, hydroxyl, epoxy GO.X- ray diffraction radical oxygen containing functional groups (XRD) and transmission electron microscopy (TEM) characterization results, GO layered structure is separated, by calculation, the layer distance of 0.835 nm.2. by physical method mixed preparation GO-MWCNTs The best quality of hybrid.GO and MWCNTs is 4:1. infrared (FT-IR) and scanning electron microscopy (SEM) characterization results clearly showed that the GO and MWCNTs have the hybrid.XRD test results show that the GO-MWCNTs hybrid layer spacing of 0.847 nm, which was obviously higher than that of the interlayer spacing of the GO.3. Fe_3O_4- prepared by co precipitation method by (GO-MWCNTs) the best quality magnetic hybrid.Fe_3O_4 and GO-MWCNTs hybrid ratio of 3.2:1~3.8:1.FT-IR, SEM, thermogravimetry (TGA) test shows that Fe_3O_4 have been dispersed on the surface of.4. GO-MWCNTs hybrid using PLL to Fe_3O_4- through the Fe-O coordination bond (GO-MWCNTs) composite surface grafting treatment, preparation of magnetic nano composite PLL-Fe_3O_4- (GO-MWCNTs).FT-IR materials, TGA results show that PLL has been grafted onto Fe_3O_4- via amide bond (GO-MWCNTs) joined the.PLL surface of the magnetic hybrid not only greatly improve the adsorption activity of composite material Site, but also improve the composite material dispersed in water. The composite material for the cationic dye methylene blue (MB), lemon yellow dye and heavy metal anion ion Pb (II) adsorption and separation, the experimental results show that under the optimal adsorption conditions, PLL-Fe_3O_4- (GO-MWCNTs) MB of the maximum adsorption capacity calculation 561.80mg g-1, the maximum adsorption capacity calculated tartrazine was 775.19 Mg - g-1, Pb (II) to calculate the maximum adsorption capacity for 1038.42mg g-1.5. using SA Fe_3O_4- (GO-MWCNTs) composite materials for surface modification, preparation of magnetic SA-Fe_3O_4- (GO-MWCNTs).FT-IR nanocomposites, TGA results show that SA has. Embedded Fe_3O_4- (GO-MWCNTs) hybrid magnetic beads. The formation of the composite beads for MB solution containing two valence and heavy metal ion Cu (II), Cd (II), Ni (II) adsorption and separation of the test solution. Experimental results show that the selection of the optimum absorption With conditions, the maximum adsorption capacity of the composite ball of MB calculation is 632.91 Mg - g-1, the price of two heavy metal ions adsorption capacity of the size of Cu (II) Cd (II) Ni (II).6. PGA of Fe_3O_4- (GO-MWCNTs) composite surface grafting treatment, preparation of magnetic PGA-Fe_3O_4- (GO-MWCNTs).FT-IR nano composite materials, TGA results show that PGA has been grafted to the surface of Fe_3O_4- (GO-MWCNTs) composite material. The magnetic composite material for heavy metal ions on Cu (II), Cd (II), Ni (II) adsorption and separation experiments. The experimental results show that the adsorption process of heavy metal ions will follow the quasi two order kinetic model and the adsorption isotherms are consistent with the Langmuir model, the experimental results show that the optimal adsorption conditions were selected, PGA-Fe_3O_4- (GO-MWCNTs) adsorption capacity of heavy metal ions on Cd (II) Cu (II) Ni (II).

【学位授予单位】：济南大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB33;TQ424

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