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1.
通过FTIR、FR分析了天祝腐植酸吸附重金属Ni2+离子前后的红外光谱、荧光强度的变化,对重金属离子Ni2+进行了吸附性能及机理研究.结果表明:在室温条件下(20℃~ 25℃),吸附最佳pH=6,吸附平衡时间约为5h.符合Freundlich吸附模型,相关系数R=0.9998,特性常数n为2.49.腐植酸对Ni2+有较好的吸附性能,其吸附过程可用Ho准二级反应动力学模型描述.  相似文献   

2.
提取腐植酸后的残渣对Cu~(2+)的吸附性能研究   总被引:1,自引:0,他引:1  
研究了天祝褐煤中提取腐植酸后的残渣对Cu2+的吸附性能。结果表明,在室温(20~25℃)条件下,吸附平衡时间约为5h,吸附最佳pH为5~6,相关系数R为0.9889,特性常数n为3.449。吸附符合Freundfich吸附等温式,提取腐植酸后的残渣对Cu2+有较好的吸附性能,其吸附过程可用Ho准二级反应动力学模型描述。  相似文献   

3.
选取玉米秸秆为原料, 经过缺氧炭化制备玉米秸秆生物炭, 并以聚乙烯亚胺(PEI)负载于生物炭表面, 制备PEI功能化秸秆生物炭, 研究了其对水中Cr 6+的吸附性能和机理. 结果表明, 在吸附剂添加量相等条件下, PEI碱性生物炭(PBC)对Cr 6+的吸附效率明显高于PEI酸性生物炭(HBC)和原始生物炭(CBC). PBC对水中Cr 6+的最大吸附量为386.3 mg/g, 吸附平衡时间为300 min; 当pH=2.0左右时, 对Cr 6+的吸附效率最大达到95.94%. 因此, PBC可作为一种高效去除水中Cr 6+的吸附剂.  相似文献   

4.
研究了花生壳对Cr6+吸附的动力学特点,探讨了Cr6+,初始浓度、溶液的pH值及温度对Cr6+吸附效果的影响.结果表明,在Cr6+初始浓度<100mg/L,溶液的pH值≤2.0,温度<40℃的操作条件下,该方法具有实际应用的可能性.此吸附过程符合Lagergren准二级动力学方程,吸附等温线符合Langmuir和Freundlich模式.  相似文献   

5.
腐植酸对砷的吸附作用研究   总被引:4,自引:0,他引:4  
腐植酸中含有大量的极性基团,对金属离子有较强的吸附性能。运用氢化物-原子荧光光谱法,以泥炭腐植酸为原料,研究了腐植酸对砷(V)离子的吸附作用和腐植酸吸附剂中砷的回收,并得出了最佳的吸附和脱附条件。实验考察了酸度、时间分别对吸附和脱附的影响。结果表明,泥炭腐植酸对砷吸附的最佳模型为Freundlich吸附方程,当溶液成中性时腐植酸对砷的吸附量较大且趋于平稳。砷的浓度为1μg/mL,溶液的pH值为7,吸附时间控制在55min时,吸附效果最佳,最大吸附率为85.49%。脱附的最佳条件为:pH值14,脱附时间20min。  相似文献   

6.
以环氧环己烷作为改性单体,通过环氧氯丙烷与环氧环己烷阳离子开环聚合获得分子量约为3000的共聚醚主链。然后以联苯为介晶基元、亚氨基二乙酸为末端螯合基团,成功合成了一种新型结构的侧链液晶聚醚螯合树脂。在对其结构鉴定以及基础物理性质测定的基础上,系统地研究了该树脂对水中Cu2+吸附的影响因素、再生性能、吸附选择性、吸附模型以及吸附动力学。结果表明,该树脂对Cu2+具有良好的吸附性能、再生性能和选择性,其对水中Cu2+的吸附为Langmuir单分子层吸附,吸附过程符合准二级动力学模型。  相似文献   

7.
采用分散聚合法通过共聚、开环反应,对纳米Fe3O4进行表面功能化修饰,得到富含NH2官能团的纳米磁性高分子复合材料.通过透射电镜(TEM)、振动样品磁强计(VSM)、热重差热分析(TGA)、X射线衍射(XRD)、红外光谱(IR)等对其进行表征,着重研究了其作为吸附剂对Cr(Ⅵ)的吸附性能.结果表明:该吸附剂对Cr(Ⅵ)的吸附能在10 min内达到平衡;废水溶液pH值能显著影响吸附剂对Cr(Ⅵ)的吸附效果,pH为2.5时效果最佳.废水中Cr(VI)的初始浓度、吸附时间、温度等因素对吸附效果均有不同程度的影响.结合相应pH值下Cr(Ⅵ)的形态分布,探讨了这种新型材料对Cr(Ⅵ)的吸附机理.结果表明:其吸附机理及吸附容量与废水中Cr(Ⅵ)的离子形式有关;吸附过程以离子交换与静电引力为主.等温吸附数据符合Langmuir模型,T=308 K pH=2.5,V=40 mL时,吸附剂的饱和吸附容量qm=25.58 mg/g.吸附为吸热过程,焓变△H=8.64 kJ/mol.  相似文献   

8.
本文以硅胶为载体,通过氯丙基三乙氧基硅烷(CPTS)将2-氨基吡啶负载到硅胶表面,得到硅胶负载氨基吡啶(SG-AP)吸附材料,通过红外光谱、元素分析对其结构进行了表征。研究了SG-AP对Ag+的吸附性能,考察了溶液pH值、接触时间、温度及金属离子初始浓度等因素对吸附性能的影响。结果表明,对Ag+的最佳吸附pH值为6。吸附动力学表明,对Ag+的吸附符合准二级动力学模型,为液膜扩散控制过程。等温吸附表明吸附过程可用Langmuir模型描述,为单分子层吸附。SG-AP对Ag+吸附的热力学参数表明,吸附过程是自发、吸热的过程。  相似文献   

9.
对1.0~1.6mm的新疆核桃壳进行改性,在其表面引入氨基基团,以此作为吸附剂,研究其对含Cr(VI)模拟废水的静态吸附性能。实验结果表明,改性核桃壳对Cr(VI)有很好的吸附作用,对于50m L浓度为20mg/L模拟水样,当温度为25℃,水样初始p H值为5.89,吸附剂用量为0.50g,吸附时间为180min时,Cr(VI)的去除率可以达到98.6%,并且随着体系温度的升高,改性核桃壳对Cr(VI)的吸附量逐渐增加。吸附等温线拟合结果表明,Langmuir吸附等温模型能更好地描述上述吸附过程。  相似文献   

10.
以木素磺酸钙为原料,利用反相悬浮聚合技术在一种价廉无毒的介质相中制备出球状木质素基离子交换树脂,并讨论了它对Cr3+的吸附性能。结果表明,树脂对低浓度Cr3+的吸附效果好,前期吸附速度快,40min后吸附速率趋缓;升高温度能明显提高前期吸附速率,饱和吸附量约为60mgCr3+/g干树脂,而且树脂在较宽的弱酸性范围内表现出良好的吸附性能。  相似文献   

11.
5A沸石在水溶液中对氯化十四烷基吡啶的吸附   总被引:1,自引:0,他引:1  
表面活性剂在固液界面上的吸附作用是十分重要的课题,为此我们开展了这方面的研究[1-3]。沸石结构规则,孔大小均匀,具有特殊的吸附性质。近年来由于作为合成洗涤剂助剂的三聚磷酸钠可使水质富营养化,故国内外都在研究洗涤剂的低磷化措施。  相似文献   

12.
The adsorption of zinc and cyanide from cyanide effluents onto strong and weak basic anion exchange resins was studied in a batch adsorption system. Factors influencing the adsorption rates such as resin selection, resin amounts, contact time and temperature were studied and scanning electron microscopy-energy disperse spectroscopy(SEM-EDS) was used in the analysis. The present study shows that the adsorption capacity of resin 201×7 is better than that of resin 301. The adsorption process was relatively fast and came to equilibrium after 60 min. The kinetic data were analyzed with three models and the pseudo-second-order kinetic model was found to agree with the experimental data well. The equilibrium data could also be described well by Langmuir isotherm model. Thermodynamic parameters such as enthalpy change(ΔH0), free energy change(ΔG0) and entropy change(ΔS0) were calculated and the adsorption process was spontaneous and endothermic.  相似文献   

13.
气体超临界吸附研究进展   总被引:17,自引:0,他引:17  
周亚平  杨斌 《化学通报》2000,63(9):8-13
综述了近年来国内外学者对超临界气体在固体表面吸附的研究情况。指出了气体在临界温度以上吸附与临界温度以下吸附的不同之处;对现行的关于超临界气体的吸附理论研究进行了讨论,并在此基础上提出了研究中存在的总是及进一步的研究方向。  相似文献   

14.
Graphene oxide (GO) is widely used in various fields such as improving the performance of cement-based materials and making composite materials due to its large specific surface area and abundant oxygen-containing functional groups. However, it has also caused water pollution. To remove GO in aqueous solution, sepiolite (SEP) was used to adsorb it. The effects of pH, adsorbent quality, GO concentration, temperature and adsorption time on the ability of SEP to adsorb GO were investigated. The materials were characterized by SAP and laser particle size analyzer, and the adsorption performance and mechanism of SEP for GO were further analyzed by XRD, FTIR, SEM, TEM, XPS, AFM, and Zeta potential microscopic tests. The results showed that: 1) Under the conditions of temperature 303 K, pH = 3, adsorbent mass 30 mg, and initial concentration of GO 100 mg/L, the adsorption effect was the best, and the adsorption rate reached 94.8 %. 2) The adsorption reached equilibrium at 2160 min, and the adsorption process was more in line with the pseudo-second-order adsorption kinetic equation, and the adsorption behavior was controlled by chemical effects. 3) The adsorption of SEP to GO is more consistent with the Langmuir and Temkin adsorption isotherm model, and the reaction is a spontaneous, endothermic, and entropy-increasing process. Experiments showed that SEP had a strong adsorption capacity for GO, which provides a reference for the treatment of toxic GO in aqueous solution and the realization of water ecological protection.  相似文献   

15.
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.  相似文献   

16.
We investigated by Ar and Kr adsorption isotherm techniques for two kinds of carbon single-wall nanotube bundles prepared by different synthesis methods. Despite the difference in the adsorption capacity in the two samples, the adsorption mechanisms are similar, which indicates that the same adsorption sites are involved for Ar and Kr. We have already measured a similar difference in the adsorbed amount in these samples studied by a low-temperature heat-capacity technique, i.e., for the case of 4He as adsorbate. These results cannot be easily explained by only taking into account the topology of the bundles if all tubes are closed-ended. A larger spread of effective surface areas among different sources of samples is reported in the literature data.  相似文献   

17.
磷酸铝吸附除水中氟的研究   总被引:7,自引:0,他引:7  
采用静态吸附法研究了比表面为308m2/g的无定形磷酸铝吸附除氟性能,研究了接触时间、pH值、吸附剂量等对吸附的影响。结果表明,磷酸铝吸附除氟高效、迅速,30min内可以接近最大吸附量。对含氟50mg/g的溶液,优化条件下的最大除氟率约93%。研究了吸附与溶液pH的关系,得到了优化pH值并解释了吸附机理。吸附的最佳pH值约为5.5。用拟二级动力学方程描述了吸附速率并计算了速率常数。用Langmuir方程拟合了吸附等温线,计算的饱和吸附量为53.5mg/g。吸附剂量对分配系数的影响表明吸附剂表面是不均匀的。  相似文献   

18.
An equation derived previously14 for adsorption from binary liquid mixtures composed of molecules of different sizes on heterogeneous solids has been reexamined. Verification of this equation by means of numerical simulation showed its applicability for describing the liquid adsorption onto weakly and strongly heterogeneous surfaces.
Eine Isothermen-Gleichung für die Adsorption aus binären flüssigen Gemischen an heterogenen Oberflächen fester Körper unter Berücksichtigung der Differenzen in den Molekülgröen der Komponenten und ihre numerische Verifikation
Zusammenfassung Es wurde die früher14 abgeleitete Isothermen-Gleichung der Adsorption aus binären flüssigen Gemischen an heterogenen Oberflächen fester Körper abermals untersucht. Durch Computersimulation wurde gezeigt, daß diese Gleichung den obengenannten Prozeß, der sich sowohl an schwach wie auch an stark heterogenen Oberflächen vollzieht, gut beschreibt.
  相似文献   

19.
本文研究可再生甲壳质自水中吸附有机酸的特性,讨论了可再生甲壳质所含活性基团和吸附环境的温度对吸附有机酸的影响。实验结果表明,可再生甲壳质的吸附活性中心是自由胺基;可再生甲壳质吸附草酸的过程是放热变化,升温不利吸附,吸附邻苯二甲酸的过程是吸热变化,升温有利吸附。这一规律,为设计最佳工艺流程提供了有价值的数据。  相似文献   

20.
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