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1.
在利用静电喷射一步法获得壳聚糖(CS)磁性微球(Fe3O4/CS)的基础上,对Fe3O4/CS进行高温炭化和碱活化处理获得活性磁性多孔炭球(A-Fe3O4/C),并对A-Fe3O4/C吸附水中亚甲基蓝(MB)分子的性能进行了研究。在利用扫描电子显微镜、红外吸收光谱仪、比表面分析仪对制备微球的形貌和结构进行分析的基础上,深入研究溶液pH、吸附时间、温度以及活化剂种类等因素对A-Fe3O4/C吸附性能的影响。研究结果表明,A-Fe3O4/C对MB的吸附量随着pH值的增加而增大,且经KOH活化后的A-Fe3O4/C对MB表现出较优的吸附性能。A-Fe3O4/C对MB的吸附过程符合伪二级动力学方程和Langmuir等温线模型,理论最大吸附容量可达300.6 mg·g-1。此外,A-Fe3O4/C表现出良好的重复利用性能,6次循环后对MB的去除率没有明显下降。  相似文献   

2.
设计并合成了一种以磁性纳米粒子为核,聚合物为中间层,金属有机骨架材料为外层的三层结构磁性复合材料(Fe3O4@PAA@ZIF 8)。首先利用溶剂热法制备Fe3O4纳米粒子,然后通过蒸馏沉淀聚合法在Fe3O4纳米粒子表面包覆聚丙烯酸(PAA)层,最后通过原位沉积法在PAA外部包覆ZIF 8。在对Fe3O4@PAA@ZIF 8的组成和结构进行表征的基础上,深入研究其对孔雀石绿(MG)的吸附性能。透射电子显微镜(TEM)显示 Fe3O4@PAA@ZIF 8 具有明显的三层结构,Fe3O4的平均粒径为 117nm,PAA 层厚度约为 17 nm,ZIF 8层的厚度约为 14 nm。Fe3O4@PAA@ZIF 8对 MG 的吸附量随着 pH 的升高而增大,吸附过程符合准二阶动力学模型和 Langmuir等温吸附模型。此外,Fe3O4@PAA@ZIF 8还表现出良好的重复利用性能,8次循环利用后对MG(500 mg·L-1)的最大吸附量仍可达982 mg·g-1。  相似文献   

3.
为了提高壳聚糖的多染料吸附性能并使其便于固液分离,采用共沉淀法制备了壳聚糖、磁铁矿纳米颗粒、氧化石墨烯复合磁性吸附剂(CS/Fe3O4/GO)。系统的结构表征显示,CS包覆的Fe3O4磁性纳米颗粒均匀地分布在GO的表面。CS/Fe3O4/GO具有高达42.5 emu·g-1的室温铁磁性,因此可在外加磁场中实现高效固液分离。研究表明,CS/Fe3O4/GO对亚甲基蓝(MB)、甲基橙(MO)和刚果红(CR)等多种染料具有良好的吸附性能,溶液的pH、初始浓度和吸附时间对其多染料吸附性能具有显著影响。在最佳条件下,CS/Fe3O4/GO对MB、MO和CR的吸附量分别达到210.6、258.6和308.9 mg·g-1。CS/Fe3O4/GO具有优异的循环利用性能,经5次循环后仍能保留90%以上的原始吸附量。采用吸附等温线和吸附动力学对CS/Fe3O4/GO的多染料吸附性能进行了拟合分析,并详细讨论了其吸附机理。  相似文献   

4.
利用液相沉淀法可控合成了均匀的棒状CuFe4Ox催化剂。通过原位X射线粉末衍射(XRD)、高分辨透射电子显微镜(TEM)及程序升温还原(TPR)等手段表征其晶相结构、形貌和还原性能。通过还原棒状CuFe4Ox获得Cu0/Fe3O4纳米棒,原位X射线光电子能谱(XPS)用于确定Cu0/Fe3O4表面的相组成。通过液相沉淀法制备棒状CuFe4Ox,在120℃保持3 h后加入Na2CO3溶液至pH等于9时所得棒状形貌最为规整。以异戊醇脱氢反应作为探针反应,比较了Cu0/Fe3O4纳米棒和Cu0/Fe3O4纳米颗粒的催化反应性能,发现Cu0/Fe3O4纳米棒比Cu0/Fe3O4纳米粒子具有更好的活性和稳定性,表明棒状Fe3O4担载的Cu纳米粒子具有更好的结构稳定性。  相似文献   

5.
采用一种改进的共沉淀法制备了纳米磁铁矿(Fe3O4)及Ni2+掺杂磁铁矿(NixFe3-xO4,x=0.1,0.3,0.6),用X-射线衍射(XRD)、扫描电镜(SEM)、氮气物理性吸附、酸碱滴定等手段对产物进行了表征,用平衡吸附法研究了4种样品对Pb(Ⅱ)离子的吸附容量及吸附模型。结果表明,Fe3O4和3种NixFe3-xO4均为近似球形的单相晶质纳米颗粒;与Fe3O4比较,NixFe3-xO4的颗粒尺寸变小、表面电荷零点和pH=5.0时的表面正电荷量降低;样品的孔体积、比表面积和表面分形度以及表面羟基含量都随产物中Ni2+掺杂量的增加而升高。4种样品对Pb(Ⅱ)的等温吸附数据均适合用Langmuir模型拟合(R2=0.9942~0.9858),其相关系数的大小表现为:Fe3O4>Ni0.1Fe2.9O4>Ni0.3Fe2.7O4=Ni0.6Fe2.4O4;Freundlich模型对样品等温吸附Pb(Ⅱ)的实验数据拟合度较低(R2=0.9813~0.9477),4种样品的Freundlich相关系数的大小关系与Langmuir相关系数相反。初始pH=5.0时,Fe3O4,Ni0.1Fe2.9O4,Ni0.3Fe2.7O4和Ni0.6Fe2.4O4对Pb(Ⅱ)的最大吸附容量分别为6.02,6.68,7.29和8.34mg·g-1。可见,NixFe3-xO4(尤其是Ni2+掺杂量较高的产物)对水环境中重金属Pb(Ⅱ)的去除能力明显高于Fe3O4。  相似文献   

6.
利用液相沉淀法可控合成了均匀的棒状CuFe4Ox催化剂。通过原位X射线粉末衍射(XRD)、高分辨透射电子显微镜(TEM)及程序升温还原(TPR)等手段表征其晶相结构、形貌和还原性能。通过还原棒状CuFe4Ox获得Cu0/Fe3O4 纳米棒,原位X射线光电子能谱(XPS)用于确定Cu0/Fe3O4 表面的相组成。通过液相沉淀法制备棒状CuFe4Ox,在120℃保持3 h后加入Na2CO3溶液至pH等于9时所得棒状形貌最为规整。以异戊醇脱氢反应作为探针反应,比较了Cu0/Fe3O4 纳米棒和Cu0/Fe3O4 纳米颗粒的催化反应性能,发现Cu0/Fe3O4 纳米棒比Cu0/Fe3O4 纳米粒子具有更好的活性和稳定性,表明棒状Fe3O4 担载的Cu纳米粒子具有更好的结构稳定性。  相似文献   

7.
魏世勇  杨小洪 《无机化学学报》2013,29(12):2615-2622
采用一种改进的共沉淀法制备了纳米磁铁矿(Fe3O4)及Ni2+掺杂磁铁矿(NixFe3-xO4,x=0.1,0.3,0.6),用X-射线衍射(XRD)、扫描电镜(SEM)、氮气物理性吸附、酸碱滴定等手段对产物进行了表征,用平衡吸附法研究了4种样品对Pb(Ⅱ)离子的吸附容量及吸附模型。结果表明,Fe3O4和3种NixFe3-xO4均为近似球形的单相晶质纳米颗粒;与Fe3O4比较,NixFe3-xO4的颗粒尺寸变小、表面电荷零点和pH=5.0时的表面正电荷量降低;样品的孔体积、比表面积和表面分形度以及表面羟基含量都随产物中Ni2+掺杂量的增加而升高。4种样品对Pb(Ⅱ)的等温吸附数据均适合用Langmuir模型拟合(R2=0.9942~0.9858),其相关系数的大小表现为:Fe3O4>Ni0.1Fe2.9O4>Ni0.3Fe2.7O4=Ni0.6Fe2.4O4;Freundlich模型对样品等温吸附Pb(Ⅱ)的实验数据拟合度较低(R2=0.981 3~0.947 7),4种样品的Freundlich相关系数的大小关系与Langmuir相关系数相反。初始pH=5.0时,Fe3O4,Ni0.1Fe2.9O4,Ni0.3Fe2.7O4和Ni0.6Fe2.4O4对Pb(Ⅱ)的最大吸附容量分别为6.02,6.68,7.29和8.34 mg·g-1。可见,NixFe3-xO4(尤其是Ni2+掺杂量较高的产物)对水环境中重金属Pb(Ⅱ)的去除能力明显高于Fe3O4。  相似文献   

8.
采用溶胶-凝胶法和水热法(HTM)合成了Fe3O4@SiO2@TiO2-Co/rGO复合纳米粒子(磁性光催化剂),通过X射线衍射、扫描电子显微镜及其能量分散光谱和UV-vis漫反射光谱对产物进行了表征分析.研究了Co掺杂量、溶液pH值、亚甲基蓝(MB)溶液初始浓度以及干扰离子(例如Cl-、SO42-、CO32-)等因素对MB降解的影响,并对磁性光催化剂的可重复使用性进行了分析.正常实验条件下(pH=7,[MB]=10 mg/L,磁性光催化剂用量=0.1 g/50 mL),150 min内MB最大去除率达到98.24%.干扰离子影响MB降解次序为CO32- < Cl- < SO42-,磁性光催化剂重复使用7次MB光降解率仅下降7.07%,新型磁性光催化剂具有良好的MB降解性能和较高的重复使用性能.  相似文献   

9.
为提高具抗凝血性能的阿魏酸分子在水中的溶解性进而提高其药效,利用DBI(3,4-二羟基苯甲醛)、PEG(聚乙二醇4000)和纳米Fe3O4,采用接枝的方法制备了水溶性纳米Fe3O4-DBI-PEG-阿魏酸抗凝血杂化材料,用IR、1H NMR、TG、SEM、TEM、VSM和粒度测试方法表征了产物。结果表明阿魏酸(FA)接枝在了经过DBI-PEG活化后的纳米Fe3O4氧化物表面。杂化材料具有良好的水溶性(溶解度大于10 mg·mL-1)和顺磁性。抗凝血试验表明相同条件下杂化材料的抗凝血时间和复钙时间比阿魏酸要长,杂化材料的活化部分凝血活酶时间(APTT)和凝血酶原时间(PT)比空白组要长,杂化材料的抗凝血时间随浓度的增大而延长。  相似文献   

10.
为提高具抗凝血性能的阿魏酸分子在水中的溶解性进而提高其药效,利用DBI(3,4-二羟基苯甲醛)、PEG(聚乙二醇4000)和纳米Fe3O4,采用接枝的方法制备了水溶性纳米Fe3O4-DBI-PEG-阿魏酸抗凝血杂化材料,用IR、1H NMR、TG、SEM、TEM、VSM和粒度测试方法表征了产物。结果表明阿魏酸(FA)接枝在了经过DBI-PEG活化后的纳米Fe3O4氧化物表面。杂化材料具有良好的水溶性(溶解度大于10 mg·mL-1)和顺磁性。抗凝血试验表明相同条件下杂化材料的抗凝血时间和复钙时间比阿魏酸要长,杂化材料的活化部分凝血活酶时间(APTT)和凝血酶原时间(PT)比空白组要长,杂化材料的抗凝血时间随浓度的增大而延长。  相似文献   

11.
为了提高壳聚糖的多染料吸附性能并使其便于固液分离,采用共沉淀法制备了壳聚糖、磁铁矿纳米颗粒、氧化石墨烯复合磁性吸附剂(CS/Fe3O4/GO)。系统的结构表征显示,CS包覆的Fe3O4磁性纳米颗粒均匀地分布在GO的表面。CS/Fe3O4/GO具有高达42.5 emu·g-1的室温铁磁性,因此可在外加磁场中实现高效固液分离。研究表明,CS/Fe3O4/GO对亚甲基蓝(MB)、甲基橙(MO)和刚果红(CR)等多种染料具有良好的吸附性能,溶液的pH、初始浓度和吸附时间对其多染料吸附性能具有显著影响。在最佳条件下,CS/Fe3O4/GO对MB、MO和CR的吸附量分别达到210.6、258.6和308.9 mg·g-1。CS/Fe3O4/GO具有优异的循环利用性能,经5次循环后仍能保留90%以上的原始吸附量。采用吸附等温线和吸附动力学对...  相似文献   

12.
Amino group-functionalized Fe3O4 is loaded on a coordination complex-modified polyoxometalate nanoparticle. In this composite material, Fe3O4 and coordination complex-modified polyoxometalate are connected with intense hydrogen bonds as suggested by FTIR. This composite material exhibits excellent methylene blue (MB) adsorption, with adsorption capacity of 175.5 mg g?1. It also possesses selective separation ability between cationic and anionic dye molecules. In binary solution of MB and methyl orange (MO), MB adsorption efficiency reaches 75%, but it exhibits almost no effect on the adsorption of methyl orange. The saturation magnetization value of this composite material is 18.89 emu g?1, allowing magnetic separation, which facilitates the recycle and reuse of this composite adsorbent.  相似文献   

13.
Novel magnetic titanium dioxide nanoparticles decorated with methyltrimethoxysilane (Fe3O4@TiO2‐MTMOS) were successfully fabricated via a sol–gel method at room temperature. The synthesized material was characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, thermogravimetric analysis and vibrating sample magnetometry. The removal efficiency of the adsorbent was evaluated through the adsorption of methylene blue (MB) dye from water samples. The adsorption isotherm and kinetics were evaluated using various models. The Langmuir model indicated a high adsorption capacity (11.5 mg g?1) of Fe3O4@TiO2‐MTMOS. The nanocomposite exhibited high removal efficiency (96%) and good regeneration (10 times) compared to Fe3O4 and Fe3O4@TiO2 at pH = 9.0. Based on the adsorption mechanism, electrostatic interaction plays a main role in adsorption since MB dye is cationic in nature at pH = 9, whereas the adsorbent acquired an anionic nature. The newly synthesized Fe3O4@TiO2‐MTMOS can be used as a promising material for efficient removal of MB dye from aqueous media.  相似文献   

14.
In this study, Fe3O4-ZrO2 functionalized with 3-aminopropyltriethoxysilane (Fe3O4-ZrO2@APS) nanocomposite was investigated as a nanoadsorbent for the removal of Cd(II), Cu(II), Mn (II) and Ni(II) ions from aqueous solution and real samples in batch mode systems. The prepared magnetic nanomaterials were characterized using X-ray powder diffraction (XRD), scanning electron microscopy/energy dispersion x-ray (SEM/EDX) Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). Factors (such as adsorbent dose and sample pH) affecting the adsorption behavior of the removal process were studied using the response surface methodology. Under optimized condition, equilibrium data obtained were fitted into the Langmuir and Freundlich isotherms and the data fitted well with Langmuir isotherms. Langmuir adsorption capacities (mg/g) were found to be 113, 111, 128, and 123 mg/g for Cd, Cu, Ni and Mn, respectively. In addition, the adsorption kinetics was analyzed using five kinetic models, pseudo-first order, pseudo-second order, intraparticle diffusion and Boyd models. The adsorbent was successfully applied for removal of Cd(II), Cu(II), Mn (II) and Ni(II) ions in wastewater samples.  相似文献   

15.
The magnetic poly(ethylene glycol dimethacrylate-n-vinylimidazole) (Fe3O4@poly (EGDMA@VIM)) microspheres were prepared by suspension polymerization method using magnetite Fe3O4 nano-powder and the porosity, morphology, chemical composition and structure of the magnetic polymer microspheres were characterized. The specific surface area and swelling ratio of the Fe3O4@poly(EGDMA@VIM) microspheres were found to be 278.6?m2·g1 and 48%, respectively. The Fe3O4@poly(EGDMA@VIM) microspheres were used as an adsorbent for phenol removal. The effects of the parameters such as adsorbent dosage, temperature, pH and initial concentration of phenol solutions on the adsorption were investigated. The experimental adsorption equilibrium data obtained were fitted with Langmuir, Freundlich and Dubinin-Radushkevich isotherms and the pseudo-first-order, pseudo-second-order and intra–particle diffusion kinetic models. The adsorption equilibrium data agreed well with the Freundlich isotherm and the pseudo-second-order kinetic model. The maximum capacity of the Fe3O4@poly(EGDMA@VIM) microspheres was calculated to be 33.83?mg·g1 at 298?K and natural pH from Langmuir isotherm. The Fe3O4@poly(EGDMA@VIM) microspheres were found to be reusable for removal of phenol after desorption for several times. The result indicated that the Fe3O4@poly(EGDMA@VIM) microspheres are potential candidate for removal of phenol in wastewaters.  相似文献   

16.
采用H2O2-Vc氧化还原体系引发半纤维素衍生物,以表面修饰的Fe3O4粒子作为磁性组分,利用接枝共聚方法制备了新型半纤维素基磁性水凝胶. 分别用傅里叶变换红外(FTIR)光谱、X射线光电子能谱(XPS)和扫描电子显微镜(SEM)对水凝胶的结构及形貌进行了表征,利用X射线衍射(XRD)和振动样品磁强计(VSM)对水凝胶的晶型结构及磁性能进行了分析,发现Fe3O4粒子均匀分散在凝胶网络中,半纤维素基磁性水凝胶表现出良好的顺磁性. 考察了丙烯酸/半纤维素比例、Fe3O4粒子含量及交联剂用量对水凝胶溶胀性能的影响,并探讨了该水凝胶的溶胀机理,它在pH 8 缓冲溶液中的溶胀较好符合Fickian 和Schott 动力学模型. 通过SEM和溶胀性能分析表明,随着pH值的升高水凝胶的孔径增大,水凝胶的溶胀率逐渐增大. 制备的水凝胶被用于溶菌酶吸附研究,结果表明磁性凝胶的吸附量大于非磁性水凝胶,水凝胶的吸附行为符合Freundlich 和Temkin 等温模型.  相似文献   

17.
免疫磁性纳米微球的制备与表征   总被引:1,自引:0,他引:1  
王斌 《化学通报》2015,78(9):847-850
成功制备了Fe3O4磁性纳米颗粒及二甲基丙烯酸乙二醇酯-甲基丙烯酸(EGDMA-MAA)共聚物包覆的Fe3O4磁性复合微球。将吲哚美辛抗体固定在复合微球表面,形成了Fe3O4(核)/聚合物-抗体(壳)的复合免疫磁性颗粒。XRD结果表明,制备的Fe3O4的晶型为反立方尖晶石型且纯度较高;TEM表征表明Fe3O4粒径较为均匀,平均粒径为12nm;磁性复合微球的平均直径为460nm。制备的Fe3O4磁性纳米颗粒和磁性复合微球有较强的磁响应强度,其饱和磁化率分别为49.16和8.38emu/g,能够满足磁性分离的要求。FT IR验证了磁性复合微球中羧基特征峰的存在,表明羧基成功连接在磁性微球上面。通过碳二亚胺/N-羟基琥珀酰亚胺(EDC/NHS)活化法将微球表面羧基活化并成功与抗吲哚美辛抗体交联。  相似文献   

18.
In this work, we report the development of novel amino-functionalized Fe3O4 hybrid microspheres adsorbent from a facial and one-step solvothermal route by using FeCl3·6H2O as a single iron source and 3-aminophenoxy-phthalonitrile as ource of amino groups. During solvothermal process, the nitrile groups of 3-aminophenoxy-phthalonitrile would bond with the Fe3O4 through the phthalocyanine cyclization reaction to form the amino-functionalized Fe3O4 magnetic nano-material, which was confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermo-gravimetric analyzer (TGA). From the scanning electron microscope (SEM) and transmission electron microscopy (TEM) observation, the resulting monodispersed amino-functionalized Fe3O4 hybrid microspheres with the diameters of 180–200 nm were synthesized via the self-assembly process. More importantly, as-prepared Fe3O4 nano-materials with abundant amino groups exhibited high separation efficiency when they were used to remove the Cu(II) from aqueous solutions. Furthermore, the adsorption isotherms of Fe3O4 nano-material for Cu(II) removal fitted the Langmuir isotherm model, in which the calculated maximum adsorption capacity could increase from 5.51 to 16.25 mg g–1 at room temperature. This work demonstrated that the amino-functionalized Fe3O4 magnetic nano-materials were promising as efficient adsorbents for the removal of heavy metal ions from wastewater in low concentration.  相似文献   

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