新型芳香三嗪超交联多孔聚合物去除水溶液中甲基橙（英文）

有机染料,尤其是阳离子染料甲基橙(MO)是有毒有害的污染物之一,开发新型高效吸附剂去除MO具有重要意义。本文将含氮原子单体2,4-二氨基-6-苯基-1,3,5-三嗪通过一步傅克烷基化法合成了一种新型芳香三嗪超交联多孔聚合物(HAPP)。利用扫描电镜(SEM)、透射电镜(TEM)、傅里叶变换红外(FTIR)光谱、元素分析(EA)、热重分析(TGA)、固体~(13)C核磁共振(~(13)C NMR)和N2吸附-脱附等温线表征了材料。结果表明,HAPP材料是表面不规则的粗糙无定型多孔有机聚合物,具有较高比表面积(104.4 m~2·g~(-1))和良好的热稳定性。HAPP对水溶液中的染料MO有很好的吸附效果,其对MO最大吸附容量(qmax)高达249.3 mg·g~(-1),比之前一些文献报道的多孔材料MO吸附容量高。通过实验与理论计算相结合的方法详细讨论了HAPP高效吸附MO的吸附机理。5次吸附-脱附循环实验表明,HAPP对MO的去除率没有显著下降。     

三聚氰胺功能化多孔有机聚合物的合成及其对甲基橙的吸附性能

首先以对三联苯(TP)和对苯二甲酰氯(TC)为单体合成了酮基聚合物前体(TP-TC),而后基于席夫碱反应将三聚氰胺(MA)与之交联得到胺功能化的多孔有机聚合物TP-TC-MA。通过扫描电镜(SEM)、透射电镜(TEM)、傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)、氮气吸附-脱附(BET)以及零电荷点(pH_pzc)的测定等手段对合成的多孔有机聚合物进行表征。以染料废水中典型的阴离子染料甲基橙为研究对象,研究了TP-TC-MA对其吸附行为,并探讨了吸附机制。利用紫外-可见分光光度计(UV-Vis)得出目标污染物的紫外吸收光谱标准曲线,标准曲线拟合相关系数(R²)为0.999。结果表明,TP-TC-MA由于具有高比表面积(708.5 m²/g)和总孔体积(0.556 cm³/g)以及丰富的含氮基团,对阴离子染料甲基橙表现出优异的吸附性能。TP-TC-MA对水中甲基橙的吸附动力学符合准二级动力学方程,吸附平衡数据可以采用Langmuir等温吸附模型描述。经由Langmuir等温吸附模型计算得到的理论最大吸附容量为156.3 mg/g。选择性实验结果表明,TP-TC-MA对阴离子染料甲基橙具有更强的吸附作用,吸附作用机理可归结为静电相互作用、氢键和π-π相互作用等。在重复使用5次之后,TP-TC-MA对甲基橙仍保持90%以上的去除率,表明材料具有良好的稳定性和重复利用性,在染料废水处理中具有很好的应用前景。     

离子型超交联聚合物吸附罗丹明B

为了高效吸附废水中的可溶性有机染料,以4-苯胺基苯磺酸钠和苯为单体,二甲氧基甲烷为交联剂,在无水FeCl₃催化下,经过付-克反应一步合成了磺酸钠离子(―SO₃Na)修饰的超交联聚合物(HCP-SO₃Na)。通过元素分析、红外光谱、N₂吸/脱附分析、固态核磁共振波谱和热重分析对HCP-SO₃Na的结构和热性能进行了表征。结果表明,HCP-SO₃Na是一种比表面积大、热稳定性强的无定形微孔有机聚合物,比表面积为587m₂/g,微孔面积为411m₂/g。通过对阳离子染料罗丹明B(RhB)的吸附研究表明,―SO₃Na基团的引入,可增加HCP对RhB的饱和吸附量,最大吸附量达431mg/g,吸附符合准二级动力学模型和Langmuir模型,且循环吸附5次之后,吸附性能无明显降低。     

超交联多孔有机聚合物在柱固相萃取中的应用进展

超交联多孔有机聚合物(hypercrosslinked porous organic polymers, HCPs)是一类通过傅-克烷基化反应将芳香结构单元连接而制备得到的新型多孔材料,具有单体来源广泛、比表面积高、成本低廉、合成条件温和及易功能化等优点,广泛应用于气体储存、多相催化、色谱分离和有机污染物去除等领域。近年来,HCPs作为柱固相萃取吸附剂的研究较多,展现出巨大的应用潜力。基于高比表面积、优异的吸附性能、多样化的化学结构和易于化学改性等优点,HCPs材料被成功应用于不同样品基质中多种类型分析物的萃取并表现出优异的萃取性能。根据HCPs的骨架化学结构、目标分析物的性质及两者间的作用机理,我们将HCPs分为疏水型、亲水型、离子型3类,介绍了各种HCPs的特点、合成方法和在柱固相萃取中的应用。基于HCPs与分析物之间的疏水、π-π、亲水、氢键、离子交换等多种相互作用机理,HCPs萃取材料能够高效萃取和选择性富集不同种类的目标分析物,如苯脲类除草剂、氯酚类化合物、硝基咪唑、四环素、酸碱性药物等。将新型HCPs萃取与色谱、质谱等现代分析技术结合的方法已广泛应用于环境监测、食品安全和生...     

甲基橙分子印迹聚合物的制备及性能研究EI北大核心CSCD

以甲基橙(MO)为模板分子、丙烯酰胺(AM)为功能单体、乙二醇二甲基丙烯酸酯(EDMA)为交联剂、偶氮二异丁腈(AIBN)为引发剂、邻苯二甲酸二丁酯(DBP)为溶胀剂、聚苯乙烯微球为种球,通过种子溶胀法,探讨了不同溶剂制备的甲基橙分子印迹聚合物(MO-MIPs)的红外谱图及其对模板分子的吸附能力;使用最佳溶剂进行溶剂用量探讨。当溶剂用量为10 m L时,所制备的M O-M IPs对M O吸附效果最好;选取最优条件下制备的M O-M IPs,进行了最佳p H确定、斯卡查德曲线分析、热力学模型曲线拟合以及循环使用次数测试,结果最佳吸附p H为6;吸附过程中存在两类结合位点,其中高亲和力位点平衡解离常数为3.59 mg/L,最大吸附量为1.87 mg/g;低亲和力位点平衡解离常数为33.43 mg/L,最大吸附量为5.47 mg/g;热力学模型更符合弗伦德里希模型;经过8次循环利用,吸附量并没有明显的下降趋势。     

Cu(Ⅱ)印迹壳聚糖交联多孔微球去除水溶液中金属离子

研究了以Cu2+为模板的壳聚糖交联多孔微球(Cu-CSCPM)对溶液中Cu2+的吸附性能,为该材料应用于去除废水、果蔬汁等有毒重金属铜离子提供理论基础。首先制备了Cu2+印迹壳聚糖交联多孔微球,并表征了微球的一些物理化学性质;其次采用静态吸附法研究了该微球对Cu2+的吸附行为。结果发现,制得的微球表面多孔,含有活性-NH2,其含水量为69.59%,树脂骨架密度为1.22g/cm3,孔度值为73.68%,交联度为82.42%。初始浓度为60mmol/L、吸附温度40℃、pH=4.0时,Cu-CSCPM对Cu2+的饱和吸附容量为1.89mmol/g。Cu-CSCPM再生5次对Cu2+仍然具有较高吸附容量。     

超交联微孔聚合物研究进展

超交联微孔聚合物是一类重要的多孔聚合物材料, 由于其具有高比表面积、合成条件温和、单体来源广泛等优点而成为研究的热点. 根据不同阶段合成方法的差异, 超交联聚合物主要由以下三种方法制备得到: (1)含官能团聚合物前体的后交联; (2)功能化小分子单体的一步法自缩聚; (3)通过外交联剂“编织”刚性的芳香族单体. 本文介绍了超交联聚合物的发展过程, 着重对三种合成超交联聚合物的方法、同时对微孔聚合物微观形貌的控制以及其在气体储存、分离、催化等方面的应用进行了总结. 最后提出了超交联聚合物的缺陷和所面临的挑战, 并对未来超交联微孔聚合物的发展前景进行了展望, 指明了超交联聚合物发展的新方向.     

超交联多孔材料的制备及其对色氨酸的吸附行为

分别以苯、联苯和1,3,5-三苯基苯为反应单体,二甲氧基甲烷（FDA）为交联剂,1,2-二氯乙烷为反应溶剂,通过Friedel-Crafts烷基化反应,合成了一系列比表面积大的多孔芳香交联聚合物（HCP-PhH-3、HCP-PhH2-3、HCP-PhH3-3）。通过氮气吸脱附分析、热失重和红外光谱对交联聚合物的结构进行表征。结果表明,聚合物的孔结构丰富,HCP-PhH-3的比表面积可达901.50 m2/g,另外该类聚合物表现出良好的热稳定性和化学稳定性。对色氨酸的吸附研究表明,三种聚合物吸附色氨酸的吸附量顺序为HCP-PhH-3> HCP-PhH2-3> HCP-PhH3-3。经过多种溶剂的浸泡后,该类聚合物对色氨酸都表现出较好的吸附效果。HCP-PhH2-3和HCP-PhH3-3吸附色氨酸的动力学和热力学拟合曲线表明,该吸附过程属于化学反应速率控制的多层吸附过程。     

二氧化锰对酸性甲基橙作用机制的研究

用UV-Vis、IR和MS对二氧化锰吸附酸性甲基橙过程的研究结果表明,在二氧化锰和酸性甲基橙之间,除了化学性吸附之外,还有氧化还原反应发生,生成了无色的可溶于水的Mn(Ⅲ)络合物,该络合物不稳定,逐渐转化成浅橙色物质。单纯的二氧化锰吸附法,对甲基橙的去除效果并不理想,25mg/L甲基橙水样的最终色度去除率为79·5%。     

聚苯胺/凹凸棒石负载纳米铁降解水溶液中甲基橙

以聚苯胺/凹凸棒石(PANI/ATP)为载体,采用液相还原法合成了负载型纳米零价铁(nZVI),用扫描电子显微镜(SEM)、透射电子显微镜(TEM)及X射线光电子能谱分析仪(XPS)等技术手段对纳米复合材料进行表征,考察了反应时间和pH值对甲基橙降解性能的影响,对降解过程进行了动力学分析,探讨了nZVI/PANI/ATP复合材料对甲基橙的降解机理。 结果表明,nZVI/PANI/ATP复合材料在较大pH值范围内能有效降解水中甲基橙并具有降解长效性,当催化剂用量1.0 g/L,降解体积50 mL,甲基橙的浓度20 mg/L,降解时间30 min时,复合材料对甲基橙的降解率达到95.8%以上,对甲基橙的降解过程符合准二级动力学模型。     

木质素磺酸钙改性丙烯酸树脂对水中甲基橙的吸附研究

以木质素磺酸钙(LS-Ca)、丙烯酸(AA)为原料,乙二醇二甲基丙烯酸酯(EDMA)为交联剂制备了木质素磺酸钙改性丙烯酸复合吸附树脂(LSAA).采用红外光谱、扫描电子显微镜、热重分析、比表面分析和吸附实验对LSAA树脂的性能进行表征.结果显示,LSAA树脂的初始分解温度为291.2℃,具有良好的热稳定性;表面粗糙,介孔丰富,树脂表面有较丰富的羟基等活性基团.LSAA对甲基橙的吸附过程受p H值的影响,298 K,p H=3时,24 h吸附量为188.33 mg/g;Langmuir和Freundlich方程均能较好地拟合甲基橙在LSAA树脂上的吸附等温线,吸附动力学过程符合准二级动力学方程,吸附为以物理吸附为主的放热过程.KannanSundaram模型拟合说明,LSAA的吸附过程分为吸附剂表面吸附、孔道缓慢扩散及小孔缓慢扩散3个阶段,直线都不经过原点,内扩散不是控制吸附过程的唯一步骤.     

Sorbent Concentration Effect on Adsorption of Methyl Orange on Chitosan Beads in Aqueous Solutions

The adsorption of methyl orange（MO） on chitosan（CS） beads in aqueous solutions was investigated by a batch equilibration technique. Special emphasis was focused on the effect of sorbent concentration（cs） on the adsorp- tion equilibration of MO on CS beads. An obvious Cs-effect was observed in the adsorption equilibration, i.e., the ad- sorption amount（F） was declined with Cs increase. The classical Langmuir model adequately described the adsorption isotherm for each given cs. However, it could not be used to predict the cs-effect observed. The applicability of the Langmuir-SCA isotherm, a surface component activity（SCA） model equation, to fit the cs-effect data was examined. In the SCA model, the activity coefficient of sorbent surface sites, fsH2O, was assumed to be a function of cs due to the deviation of a real adsorption system from an ideal one, arisen from sorbent particle-particle interactions in real systems. The results show that the Langmuir-SCA isotherm could accurately describe the c：effect observed under the studied conditions. Furthermore, the effects of temperature（t）, pH, and electrolyte（NaNO3） concentration（ CNaNO3 ） on fsH2O were examined. The results show that fsH2O clearly decreased with increasing t（20-35℃） and pH（5-8）, but no obvious change in fsH2O was observed as CNaNO3 varied in a range 0.001-0.010 mol/L. These results give a better understanding of the cs-effect.     

Pressure Dependence of the Acid/Base Equilibria of Methyl Orange in Aqueous Solutions to 1000 bar at 20°C

The pressure dependence on the acid/base equilibria of methyl orange in aqueous solution was measured at 20 °C in the 1–1000 bar range with a newly designed flow-through spectrophotometric cell. Combined chemometric and thermodynamic analyses of the UV-Vis spectrophotometric data were used to extract the dissociation constants as well as the changes in molar volume and isothermal compressibility of methyl orange as a function of pressure. The results show that increasing the pressure promotes the deprotonation of methyl orange, with pK values ranging from 3.505 at 1 bar to 3.445 ± 0.002 at 1000 bar. Increasing the pressure also yields small negative changes in the molar volume ranging from –6.9 cm³·mol⁻¹ at 1 bar to −1.7 cm³·mol⁻¹ at 1000 bar. The isothermal compressibility of methyl orange in this pressure range was estimated using the second derivative of second and third order polynomial fits to the constants, and resulted in a constant value of –48.4 × 10⁻⁴ cm³·mol⁻¹·bar⁻¹ in the former case, but increasing values from –107 × 10⁻⁴ cm³·mol⁻¹·bar⁻¹ at 1 bar to 3.43 × 10⁻⁴ cm³·mol⁻¹·bar⁻¹ at 1000 bar in the latter case. Molar absorption coefficients for the protonated and deprotonated species were also shown to be only slightly effected by pressure changes and can be used to accurately predict the absorption spectra of methyl orange as a function of pressure.     

Fe3O4@HTlc的制备及其对甲基橙的吸附研究

采用液相非稳态共沉淀法制备了磁性镁铝类水滑石(Fe3O4@HTlc),采用透射电子显微镜、粉末X射线衍射仪、傅里叶变换红外光谱仪、振动样品磁强计、比表面分析仪、微电泳仪等对样品的形貌和结构进行了表征,并比较了 Fe3O4@HTlc和HTlc对甲基橙的吸附性能。结果表明,Fe3O4@HTlc为顺磁性、具有核-壳结构和较大比表面积、带有正电荷的近球状颗粒。甲基橙在Fe3O4@HTlc和HTlc上的吸附动力学曲线均符合准一级动力学方程;吸附等温线均符合Langmuir吸附等温式;298 K时Fe3O4@HTlc和HTlc对甲基橙的饱和吸附量分别为138.89和147.06 mg/g,但Fe3O4@HTlc对甲基橙有较强吸附推动力和较短的吸附平衡时间。二者对甲基橙的吸附量均随温度的升高和pH (5~11)的增加而降低。     

Removal of Thiram from Aqueous Solutions

In this study activated carbon was used for the removal of thiram from aqueous solutions. Adsorption experiments were carried out as a function of time, initial thiram concentration and temperature. Equilibrium data fitted well to the Freundlich and Langmuir equilibrium models in the studied concentration range. Adsorption kinetics followed a pseudo second‐order kinetic model rather than pseudo first‐order model. The results from kinetic experiments were used to describe the adsorption mechanism. Both boundary layer and intraparticle diffusion played important role in the adsorption mechanism of thiram. Thermodynamic parameters (ΔG₀, ΔH₀, and ΔS₀) were determined and the adsorption process was found to be an endothermic one. The negative values of ΔG⁰ at different temperatures were indicative of the spontaneity of the adsorption process.     

Removal of Anionic Dyes from Aqueous Solution with Layered Cationic Aluminum Oxyhydroxide

It is highly desired yet challenged to find an adsorbent with low cost and excellent performance in the removal of organic dyes from aqueous solution. Here we reported that a layered cationic aluminum oxyhydroxide material hydrothermally synthesized from the low-cost source materials of AlCl₃∙6H₂O, CaO and H₂O, known as JU-111, can meet such criterion in removing methyl orange(MO) and Congo red(CR). JU-111 shows fast adsorption kinetics[especially for CR(15 s)] and high adsorption capacity(MO:>1000 mg/g; CR:>2900 mg/g), surpassing most of the reported adsorbents. Comprehensive characterizations of the adsorption process of MO and CR revealed that both adsorptions were achieved via the anion exchange process. The characteristics of extremely low cost and excellent performance render JU-111 great potential in the practical applications in the removal of anionic dyes.     

甲基橙的光谱电化学研究

现代电化学技术，如计时电势法、计时电流法、循环伏安法，包括薄层中的各种电化学方法广泛用于研究电化学反应机理及各种后行均相化学反应动力学，并卓见成效[1-3]，但这些方法的应用，一般均需复杂的数据处理．薄层光谱电化学法把中间产物和终产物局限在薄层溶液中，可直接检测其浓度变化，相比之下，在动力学研究方面显示了其特殊的优越性[4-7]．甲基检是一种偶氨化合物，常用作酸碱指示剂，其电氧化还原性质未见报导过．本文采用薄层光谱电化学法，研究它的电极反应机理．1实验部分仪器和试剂UV－3000型紫外可见分光光度计，X－Y函数…     

On the Dissociation of Methyl Orange: Spectrophotometric Investigation in Aqueous Solutions from 10 to 90 ∘C and Theoretical Evidence for Intramolecular Dihydrogen Bonding

The dissociation of methyl orange was investigated by spectrophotometry in aqueous solutions from 10 to 90 ^∘C and by quantum chemical calculations. Combined chemometric and thermodynamic analyses of the spectrophotometric data were used to simultaneously extract the thermodynamic stabilities and the spectrophotometric attributes of the dominant methyl orange species in solutions containing less than 20.00 mmol-kg⁻¹ perchloric acid and submillimolal concentrations of methyl orange. The analyses revealed the presence of only one monomeric deprotonated and one monomeric protonated species. The spectra did not reveal any evidence for the presence of tautomeric equilibria between the protonated azo and ammonium species in the experimental range studied. Thermodynamic analyses of the temperature-dependent dissociation constants showed the reactions to be endothermic and enthalpy driven with increasing acidity and increasing temperature. All molar absorption coefficients in the 275–375 nm range can be adequately reproduced in the 10–90 ^∘C range with a set of Gauss–Lorentz parameters and used to predict the absorption spectra for any desired condition. The dominant features of the spectrophotometric attributes of the methyl orange species could also be retrieved in Time Dependent–Density Functional Theory (TD–DFT) calculations. Topological analyses of the electron density also revealed the formation of a dihydrogen bond between the azo proton and an adjacent phenyl ring hydridic hydrogen which increases the stability of the azo molecules relative to the ammonium molecule.     

多孔TiO2薄膜的表面微结构对甲基橙光催化脱色的影响

 从含聚乙二醇的钛醇盐溶胶前驱体出发,通过浸渍提拉法在玻璃表面制备了锐钛矿型多孔TiO2薄膜．随着前驱物中聚乙二醇加入量及分子量的增加,聚乙二醇热分解后在薄膜中产生气孔的数量增多,孔径增大,TiO2薄膜表面的羟基含量也增加．TiO2薄膜中引入适当大小的微孔可明显提高薄膜的光催化活性;当孔径接近400nm时,光的散射增强,透光率下降,薄膜的光催化活性降低．     

Comparative Studies on Degradation of Methyl Orange by Nanostructured Zinc and Zinc Oxide Films

Nanostructured zinc and zinc oxide films were prepared by magnetron sputtering processes and succeeded air annealing treatments. Comparison of reductive degradation rate of methyl orange (MO) by zinc films and photocatalytic degradation rate of MO by zinc oxide films was carried out. Both reductive degradation and photocatalytic degradation process of MO by zinc and zinc oxide films can be described by first order kinetic model. It was found that although MO liquid was most quickly decolorized by metallic zinc films, the mineraliza-tion of MO was not thorough. Observation of extra ultraviolet absorption peaks indicated the formation of aromatic intermediates. On the other hand, although the photocatalytic degradation rate of MO liquid by ZnO films was only as about 1/4 large as the reductive degradation rate by zinc films, no signs of aromatic intermediates were found. Moreover, it was found that partially oxidized zinc oxide film showed higher photocatalytic efficiency than the totally oxidized ZnO films. Synergy effect between zinc and zinc oxide phase in the partially oxidized films was considered to be responsible for the higher photocatalytic efficiency.