碳纳米管对水体重金属污染物的吸附/解吸性能研究进展

详细阐述了碳纳米管(CNTs)对水体中和重金属离子的吸附/解吸影响因素和吸附机理,展望了碳纳米管在环境治理方面应用前景。     

碳纳米管表面改性及其吸附水中污染物的研究进展

简述了碳纳米管的结构、性质及优异的吸附性能,介绍了碳纳米管的表面改性方法,总结了对不同目标物吸附效果的差异。表面改性有利于碳纳米管对水中重金属离子的吸附,对不同的有机污染物而言,不同的修饰官能团的吸附效果差异较大。指出了吸附竞争和提高选择性等是未来需要研究的方向。     

粉煤灰改性及其吸附水体污染物的研究进展

综述了粉煤灰常见的三类改性方法,其中包括物理改性、化学改性和联合改性。简述了每类改性方法的改性原理及具体方式,如机械研磨改性、超声波改性、酸改性、碱改性、火法改性等,阐述了每种方式的改性机理及特点区别,并结合目前国内外的研究进展,介绍了改性粉煤灰对一些水体污染物的吸附效果。总结粉煤灰的改性方法及对水体污染物的吸附效果,目的是指明粉煤灰的改性方向,为寻求更佳的改性方法以及改性粉煤灰在吸附水体污染物方面逐渐实现工业化应用提供参考。指出了现有研究中存在的问题和不足,并对未来的研究方向和发展前景进行了展望。     

碳纳米管吸附性能的研究进展

介绍了碳纳米管与吸附相关的结构及特性，综述了碳纳米管作为气相和液相吸附剂的吸附研究成果，展望了碳纳米管在吸附性能应用方面的前景。     

改性玉米芯生物炭吸附水体污染物的研究进展

生物炭是一类以生物质为原料在高度缺氧的条件下经过高温处理得到的炭材料。生物炭内部具有丰富孔洞,比表面积大,且表面化学结构丰富具有良好的吸附性能。玉米芯作为一种常见的农业废弃物,也是制备生物炭的原料之一。本文综述了以玉米芯制备生物炭,及其改性工艺的研究进展,旨在为玉米芯生物炭在应用研究提供参考。     

碳纳米管吸附水体中离子的研究进展

碳纳米管的比表面积大,孔隙结构丰富,比表面能高,是一种良好的新型纳米吸附剂。介绍了碳纳米管的性质,综述了碳纳米管吸附水体中金属离子和非金属离子的研究进展,展望了碳纳米管在废水处理方面的应用前景。     

腐植酸吸附有机污染物研究进展

腐植酸具有很强的吸附阳离子和疏水性有机污染物的能力,是一种很有前途的水和废水处理绿色材料。阳离子化合物主要通过静电作用与腐植酸中去质子化的羟基结合。一些腐植酸官能团,如醌也可以通过形成共价键与芳香胺或类似的有机化合物结合。模型计算与实验研究结果表明,腐植酸与疏水性有机物之间的相互作用主要是π–π键、疏水效应和氢键。一些研究报告的结果显示：腐植酸吸附有机污染物的效率与其疏水性有关。本文综述了有机污染物与腐植酸溶液、腐植酸粉末以及吸附在诸如铝硅酸盐和磁性材料等颗粒上的腐植酸之间的相互作用,并简要地讨论了吸附过程的热力学和动力学模型,还指出一些文献中的主要错误。     

腐殖质吸附土壤有机污染物研究进展

介绍了腐殖质对土壤中有机污染物的吸附行为。归纳了腐殖质对有机污染物的吸附机理,即共价吸附、―空穴‖吸附、氢键作用、疏水性吸附等;分析了土壤pH值、阳离子交换量(CEC)以及温度对腐殖质吸附有机污染物的影响,着重讨论了主要的吸附模型:线性吸附模型、Langmuir吸附模型、Fruendlich吸附模型、双模式吸附模型、分布式反应模型等以及适用条件;最后提出了今后研究的热点和方向:腐殖质(胡敏酸、富里酸以及胡敏素)吸附行为的全面研究,多种污染物共存体系复合研究,腐殖质对有机污染物的工程应用研究。     

碳纳米管及其复合材料在水中有机污染物去除中的应用

在人类社会高速发展的同时,一些有机污染物被排入水体中造成严重的环境污染,其中部分有机物被证明对人体和水中生物存在直接或潜在的毒性.碳纳米管作为一种结构特殊且具有良好电学、力学、化学性质的新型一维纳米材料,在水处理中得到了广泛的应用.文中总结了碳纳米管及其复合材料的制备方法,及其在吸附、高级氧化、膜分离3种工艺中的应用情...     

纳米吸附材料在新兴污染物治理中的研究进展

纳米吸附材料已成为最富有生命力的新型材料,并在新兴污染物治理与分析检测技术中扮演着重要的角色。研究者开展了碳纳米管、石墨烯、二氧化钛纳米管等吸附材料的研制、表征、吸附和脱附的特性及机理的研究,并将之应用于环境新兴污染物的治理中。根据目前碳纳米材料在水体中新兴污染物吸附的应用现状,指出仍存在吸附机理研究不足、纳米材料难分离和易流失、价格昂贵等问题。制备高质量的廉价纳米材料,开发专一、化学稳定的高效吸附-降解复合材料是今后研究的一个重要方向。     

碳纳米管氧化对水中微量异狄氏剂的吸附性能影响

碳纳米管表面经强酸氧化处理,管体发生解体,分散,形成碳纳米管胶体,用于去除水中低浓度持久性有机污染物异狄氏剂。扫描电镜观测表明,氧化后的碳纳米管团簇被分散开,碳纳米管被打断;红外光谱测试曲线表明,硝酸氧化后的碳纳米管表面引入了大量含氧官能团。氧化前后的碳纳米管对异狄氏剂的吸附实验研究表明,氧化后碳纳米管的吸附性能优于原始碳纳米管吸附性能,且等温吸附曲线均呈线性。     

Adsorption of Phenol and Basic Dye on Carbon Nanotubes/Carbon Fabric Composites from Aqueous Solution

The liquid-phase adsorption of phenol and dye (basic violet 10) onto carbon nanotube (CNT)-activated carbon fabric (ACF) composites, prepared by a catalytic chemical vapor deposition (CCVD) approach, has been investigated. The CCVD technique enables the decoration of CNTs on microscaled ACFs, creating a hierarchy CNT-ACF composite. The as-grown nanotubes were found to have a tortuous shape and to be several micrometers in length. The deposition of CNTs efficiently shifts the micropore size distribution of ACFs to mesoporosity. The adsorption isotherms for phenol and BV10 on ACF and CNT-ACF adsorbents are well characterized by the Dubinin-Radushkevich and Langmuir models. The surface accessibility, the equilibrium rate constant, and the adsorption energy are significantly enhanced due to the deposition of CNTs, as analyzed by these models. Accordingly, the existence of CNTs on ACF adsorbent plays a positive role in facilitating pore accessibility to adsorbate and providing more adsorptive sites for the liquid-phase adsorption.     

碳纳米管吸附去除水溶液中锌离子的性能

研究了碳纳米管对水溶液中锌离子的吸附去除性能.结果表明:纯化的碳纳米管对锌离子的去除效果明显高于未纯化的碳纳米管,在25 mL、50 mg/L的锌离子溶液中当其用量为0.1 g时,纯化的碳纳米管锌离子的吸附去除率达94.8%;吸附60 min达到平衡;在中性和弱碱性溶液中的去除率大于酸性溶液.     

磁性多壁碳纳米管吸附处理甲基橙模拟废水的研究

对多壁碳纳米管进行纯化处理后采用化学共沉淀法制成磁性多壁碳纳米管(mMWNT),研究了其对甲基橙废水的处理效果,考察了投加量、吸附时间、pH值、温度等因子的影响。结果表明,mMWNT成功负载了Fe3O4和γ-Fe2O3;mMWNTs投加量为6 g/L时甲基橙的去除率可达99.2%;甲基橙去除率随时间呈逐渐增大趋势直至吸附平衡;实验的最佳pH为1时,去除率最高;温度为30℃时,去除率达到80%。mMWNT吸附处理甲基橙模拟废水过程符合准二级吸附动力学方程。     

碳纳米管吸附染料茜素红的性能研究

研究了碳纳米管对水中茜素红的吸附去除性能,结果表明:纯化的碳纳米管对水中茜素红的去除效果明显高于未纯化的碳纳米管,当其用量为0.1g时,纯化的碳纳米管对水中茜素红的吸附去除率达到87.3%;纯化的碳纳米管对水中茜素红的吸附在60分钟达到平衡;溶液pH值对水中茜素红的去除有一定的影响,在酸性和中性条件下的去除率大于碱性;温度升高,水中茜素红的去除率略有升高。平衡吸附量qe与平衡质量浓度pe之间的关系符合Freundlich和Langmuir等温吸附方程所描述的规律。     

Adsorption of 1,2-Dichlorobenzene from the Aqueous Phase onto Activated Carbons and Modified Carbon Nanotubes

This study aimed to describe the adsorption process of ortho-dichlorobenzene (o-DCB) onto activated carbons (ACs) and modified carbon nanotubes (CNTs) from the aqueous phase. The starting material NC_7000 carbon nanotubes were modified by chlorination (NC_C) and then by the introduction of hydroxyl groups (NC_C_B). The concentration of o-DCB in solutions was performed by UV-VIS spectrophotometry. After adsorption, the activated carbons were regenerated by extraction with organic solvents such as acetone, methanol, ethanol, and 1-propanol; the carbon nanotubes were regenerated by methanol. The degree of adsorbate recovery was determined by gas chromatography (GC) with flame ionization detection, using ethylbenzene as an internal standard. The equilibrium isotherm data of adsorption were satisfactorily fitted by the Langmuir equations. The results indicate that carbon adsorbents are effective porous materials for removing o-DCB from the aqueous phase. Additionally, activated carbons are more regenerative adsorbents than carbon nanotubes. The recoveries of o-DCB from ACs were in the range of 76–85%, whereas the recoveries from CNTs were in the range of 23–46%. Modifications of CNTs affect the improvement of their adsorption properties towards o-DCB compared to unmodified CNTs. However, the introduction of new functional groups on carbon nanotube surfaces makes the regeneration process less effective.     

Adsorption of Pyridine from Aqueous Solution by Surface Treated Carbon Nanotubes

Abstract

The surface treatment of multi‐walled carbon nanotubes (MWCNTs) with acid, heat, ultrasonic, and polyvinyl alcohol has been examined. The original CNTs and four treated CNTs were first used as adsorbents to remove pyridine from water and the adsorption isotherms of pyridine on CNTs were studied. At the same time, the effect of pH, temperature, and the adsorption kinetics on the adsorption of pyridine were also evaluated. The experiments show that the adsorption of pyridine on different CNTs is mainly a physical process and the data fit the Freundlich adsorption isotherm well. The short time needed to reach equilibrium as well as the high adsorption capacity of pyridine suggests that CNTs possess highly potential applications for pyridine removal from water.     

碳纳米管表面功能化研究进展

碳纳米管的表面功能化修饰已成为现代纳米领域的一大研究热点,对实现碳纳米管的独特约优越性起到基础性作用。文章筒述了碳纳米管（CNTs）的结构与制备方法,对碳纳米管常见的功能化修饰进行了综述,最后对碳纳米管改性高分子材料存在的问题和发展方向进行了展望。     

Kinetic and Thermodynamic Studies of the Adsorption of Several Anionic Dyes From Water Samples on Magnetite-Modified Multi-Walled Carbon Nanotubes

In this study magnetite-modified multi-walled carbon nanotubes (MMMCNTs) were used as an adsorbent for the removal of four anionic dyes from aqueous solutions. Batch studies were performed to address various experimental parameters for the removal of these dyes. Kinetic studies showed that the adsorption of dyes on MMMCNTs was almost a rapid process. Quasi equilibrium was reached in 45 min. Pseudo-first-order and pseudo-second-order models were applied to fit the experimental data and the results show that the adsorption of dyes followed the pseudo-second-order kinetic model. The thermodynamic analysis indicates an increase in the temperature resulted in increasing the dyes adsorption capacity of the adsorbent indicating the process to be endothermic.