石墨烯基复合材料对污水净化的研究进展*

石墨烯基复合材料具有较大的比表面积、较高的表面能,对污染物具有较强的吸附能力,可用于去除水中的污染物,从而达到净化污水的目的。本文综述了几种石墨烯基复合材料的制备和其对水中化学类物质,如重金属离子、有机染料和其他污染物的吸附特性,并简述了溶液的酸度、接触时间和金属离子初始浓度等对石墨烯基复合材料吸附污染物的影响。     

树脂基球状活性炭的制备及对二氧化碳吸附性能的研究

以四种离子交换树脂(两种强碱性树脂D201和D280、两种弱碱性树脂D301G和D301R)为原料,经过磺化、炭化、活化处理制备了树脂基球状活性炭。采用TG、SEM、N2吸附等对球状活性炭的收率、表面形貌、比表面积进行了表征,研究了所制球状活性炭对CO2的吸附性能。结果表明,磺化处理有助提高树脂球的炭化收率;得到的四种球状活性炭对CO2吸附性能良好,强碱性树脂球原料比弱碱性树脂球更具有优势,其中,由强碱性树脂球D201制得的树脂球状活性炭在30℃下对CO2的吸附量可达2.57 mmol/g;十次循环吸附之后,树脂球仍能保持很好的CO2吸附性能。     

载银磷酸活化剑麻基活性炭纤维的抗菌性能研究

本文利用磷酸化方法，制备各种剑麻基活性炭纤维，并利用活性炭纤维的氧化还原特性及吸附性能，在其上负载金属银，研究并比较了这些载银活性炭纤维对大肠杆菌和金黄色葡萄球菌的杀灭作用，结果表明，磷酸浓度，活化方法，活化时间，纤维的比表面积等因素的均对材料的抗菌性能有一定的影响，磷酸活化的活性炭纤维表现出强的抗菌杀菌能力，高浓度磷酸活化后的纤维抗菌能力有所提高，并且抗菌能力随活化时间的延长而增加，抗菌前后纤维上负载的银未曾大量脱落，经5次抗菌试验后材料仍显示出很强的抗菌能力。     

树脂基球状活性炭的制备及对二氧化碳吸附性能的研究

以四种离子交换树脂（两种强碱性树脂D201和D280、两种弱碱性树脂D301G和D301R）为原料,经过磺化、炭化、活化处理制备了树脂基球状活性炭。采用TG、SEM、N₂吸附等对球状活性炭的收率、表面形貌、比表面积进行了表征,研究了所制球状活性炭对CO₂的吸附性能。结果表明,磺化处理有助提高树脂球的炭化收率;得到的四种球状活性炭对CO₂吸附性能良好,强碱性树脂球原料比弱碱性树脂球更具有优势,其中,由强碱性树脂球D201制得的树脂球状活性炭在30 ℃下对CO₂的吸附量可达2.57 mmol/g;十次循环吸附之后,树脂球仍能保持很好的CO₂吸附性能。     

煤焦油沥青基纤维状活性炭的吸附性能

煤焦油沥青基炭纤维（ＣＰＣＦ）价格低廉含炭量高、易于活化,是制备纤维状活性炭（ＣＰＡＣＦ）的优良原料。本文讨论了ＣＰＣＦ的抗拉强度和活化条件对ＣＰＡＣＦ比表面积的影响。并同石油系沥青基炭纤维（ＰＰＣＦ）进行了比较。考察了不同比表面积的ＣＰＡＣＦ、ＰＰＡＣＦ和商品用颗粒活性炭（ＡＣ）对０．１ｍｏｌ／Ｌ碘溶液、０．００５ｍｏｌ／Ｌ亚早兰溶液和２９３Ｋ下三氯甲烷饱和蒸汽的吸附性能,及以上三样品在２９３Ｋ     

氧化锆-活性炭纤维复合材料的制备及其对F-吸附性能

采用水热合成法成功制备了氧化锆-活性炭纤维复合材料,并研究了其对F^-的吸附行为.表征结果表明,复合材料中氧化锆粒子成功负载于活性炭纤维上.吸附实验结果表明,负载了氧化锆的活性炭纤维对F^-有高效的去除效率,其吸附机理包括离子交换和静电作用力,吸附等温线符合Langmuir等温吸附模式,吸附动力学可用拟二级动力学模型拟合.吸附量随着溶液pH的升高而降低,共存离子Cl^-、NO₃^-和SO₄^2-对F^-在氧化锆-活性炭纤维复合材料上的吸附几乎没有影响.     

氧化锆-活性炭纤维复合材料的制备及其对F-吸附性能

采用水热合成法成功制备了氧化锆-活性炭纤维复合材料,并研究了其对F^-的吸附行为。表征结果表明,复合材料中氧化锆粒子成功负载于活性炭纤维上。吸附实验结果表明,负载了氧化锆的活性炭纤维对F^-有高效的去除效率,其吸附机理包括离子交换和静电作用力,吸附等温线符合Langmuir等温吸附模式,吸附动力学可用拟二级动力学模型拟合。吸附量随着溶液pH的升高而降低,共存离子Cl^-、NO₃^-和SO₄^2-对F^-在氧化锆-活性炭纤维复合材料上的吸附几乎没有影响。     

氯化锂活化制备活性炭及吸附锂离子性能研究

采用化学活化法,用猪血粉为前驱体和新型活化剂氯化锂活化制备锂离子活性炭（LB-AC）并进行吸附锂离子研究。用氯化锂对猪血粉进行活化后我们得到比表面积为695 m2?g-1,总孔体积为0.3 cm3?g-1的LB-AC。通过扫描电子显微镜、元素分析、X 射线衍射分析和红外光谱分析等分析手段对LB-AC表面形貌和表面基团进行表征。吸附?解吸实验结果表明,随着温度升高,锂离子的吸附容量随之增加,表明LB-AC对锂离子的吸附是一种吸热反应。当温度增加至35 ℃和45 ℃时,其吸附容量分别增加至1.41 mg?g-1和1.52 mg?g-1。锂离子的初始浓度增加,吸附容量也增加。锂的脱附随着盐酸浓度的升高而增加。LB-AC对锂离子的选择性很高,且吸附剂在碱性环境下吸附容量更高,在酸性环境下基本不吸附。     

粉末活性炭与碱式氯化铝混凝处理微污染水源水的研究

用粉末活性炭吸附与碱式氯化铝混凝相结合的工艺处理微污染生活水源水,研究活性炭种类、加入量和加入先后等因素对原水嗅味、色度和有机物等去除效率的影响。结果显示,投加40mg/L200mesh活性炭以后再进行混凝,对各种污染物的去除效果较好,对原水异嗅味、色度、浊度、矿物油和苯酚的去除率分别达到71%~90%,对CODMn、TOC和氨氮的去除率分别在47%~53%、26%~27%和10%~18%范围。     

几种植物基活性炭材料的孔结构与吸附性能比较--(Ⅰ)孔结构表征

测定了3种植物基活性炭材料：椰壳活性炭(CAC4)、剑麻茎基活性炭(SSAC)和剑麻基活性碳纤维(SACF)的氮吸附等温线，并用不同的理论方法对其孔结构进行了分析和表征．结果表明：CAC4为微孔型，孔径分布集中且大部分是0．7nm以下的板微孔：在相同条件下制备的SSAC和SACF孔分布较为相似，都呈多分散性，结构中除微孔外，还含有丰富的中孔，中孔率均超过50％以上．两者相比，SACF的中孔量和平均孔径更大，3个样品的形态特征和孔结构虽然不同，但其吸附过程都可以用微孔多段填充机理来解析。     

Adsorption of Pentafluorophenol onto Powdered,Granular, and Cloth Activated Carbons

In the present study, the adsorption of pentafluorophenol from aqueous solution onto granular activated carbon, powdered activated carbon, and activated carbon cloth has been investigated from the equilibrium and kinetic points of view. To the best of our knowledge, the removal of pentafluorophenol from aqueous solution onto activated carbon have not been reported in the literature. The experimental equilibrium data, suitably fitted by the Toth, Langmuir-Freundlich, and Redlich-Peterson isotherms, have shown that the cloth and powdered carbons exhibit the highest adsorption capacity. For all the investigated samples, the experimental kinetic data have been satisfactorily interpreted by a pseudo-second-order model. From the fitting results it has been observed that the highest rate constant and initial rate of adsorption is shown by powdered activated carbon.     

Adsorption of Carbon Dioxide on Activated Carbon

The adsorption of CO2 on a raw activated carbon A and three modified activated carbon samples B, C, and D at temperatures ranging from 303 to 333 K and the thermodynamics of adsorption have been investigated using a vacuum adsorption apparatus in order to obtain more information about the effect of CO2 on removal of organic sulfur-containing compounds in industrial gases. The active ingredients impregnated in the carbon samples show significant influence on the adsorption for CO2 and its volumes adsorbed on modified carbon samples B, C, and D are all larger than that on the raw carbon sample A. On the other hand, the physical parameters such as surface area, pore volume, and micropore volume of carbon samples show no influence on the adsorbed amount of CO2. The Dubinin-Radushkevich (D-R) equation was the best model for fitting the adsorption data on carbon samples A and B, while the Preundlich equation was the best fit for the adsorption on carbon samples C and D. The isosteric heats of adsorption on carbon samples A, B, C, and D derived from the adsorption isotherms using the Clapeyron equation decreased slightly increasing surface loading. The heat of adsorption lay between 10.5 and 28.4 kJ/mol, with the carbon sample D having the highest value at all surface coverages that were studied. The observed entropy change associated with the adsorption for the carbon samples A, B, and C (above the surface coverage of 7 ml/g) was lower than the theoretical value for mobile adsorption. However, it was higher than the theoretical value for mobile adsorption but lower than the theoretical value for localized adsorption for carbon sample D.     

Influence of Initial pH Value on the Adsorption of Reactive Black 5 Dye on Powdered Activated Carbon: Kinetics,Mechanisms, and Thermodynamics

The aim of this work was to investigate the influence of initial pH value (pH₀) on the isothermal adsorption of Reactive Black 5 (RB5) dye on commercial powdered activated carbon. Four initial pH values were chosen for this experiment: pH₀ = 2.00, 4.00, 8.00, and 10.00. In order to investigate the mechanism of adsorption kinetic, studies have been performed using pseudo-first-order and pseudo-second-order kinetic models as well as an intraparticle diffusion model. In addition, thermodynamic parameters of adsorption were determined for pH₀ = 4.00. Results of this research showed that the initial pH value significantly influences the adsorption of RB5 dye onto activated carbon. The highest adsorption capacities (q_e) and efficiencies of decolouration were observed for initial pH values of pH₀ = 2.00 (q_e = 246.0 mg g⁻¹) and 10.00 (q_e = 239.1 mg g⁻¹) due to strong electrostatic interactions and attractive π···π interactions, respectively. It was also shown that the adsorption of RB5 dye on activated carbon at all initial pH values is kinetically controlled, assuming a pseudo-second-order model, and that intraparticle diffusion is not the only process that influences on the adsorption rate.     

Gd掺杂TiO2/活性炭纤维复合材料的制备及表征

以TiCl4和Gd(NO3)3·6H2O为主要原料,采用酸催化水解法制备Gd掺杂TiO2光催化剂并通过浸涂法将其负载在活性炭纤维(ACF)表面,制得Gd掺杂TiO2/ACF复合材料。 以气相苯为模型物,考察材料的光催化活性。 利用XRD、FTIR及GC-MS对催化剂的晶相结构、光谱特征等进行了表征。 结果表明,Gd掺杂能有效抑制TiO2的晶粒生长。 Gd掺杂量、浸涂次数影响TiO2/ACF光催化活性,Gd2O3掺杂质量分数为0.48%、浸涂2次的TiO2/ACF活性最高。 在苯光催化氧化后的Gd掺杂TiO2/ACF复合材料表面未发现醌类中间产物的存在。 Gd的掺入能减缓催化剂失活,光催化反应100 min后仍能表现出较高活性。     

铜/活性炭复合材料的电化学性能研究

电极材料的开发与完善是提高电容器性能的主要途径之一.本文以烟煤为炭质原料、硝酸铜为添加剂催化制备了铜/活性炭复合材料,并对氧化铜电极、活性炭电极和铜/活性炭复合材料电极进行了循环伏安、交流阻抗和电压保持能力等电化学性能测试.结果表明,活性炭中含有适量的铜可与活性炭产生协同效应,铜/炭复合材料的电容量高于纯氧化铜电极和活性炭电极的电容量之和,含铜20%的活性炭比电容量可达67.5 F/g,是同样条件制得的无铜活性炭比电容量的1.72倍;含铜活性炭具有较好的循环性能、容量特性和较小的阻抗;但其开路电压的自保持性能有待进一步改善.     

氧化铝/碳纳米管复合材料的制备及表征

采用聚乙烯醇对碳纳米管表面进行改性，通过化学沉淀法将Al(OH)₃均匀沉积在碳纳米管表面，然后在氮气气氛下于500 ℃煅烧2 h，制备出氧化铝/碳纳米管复合材料。采用TEM、TG、DTA、XRD、IR、氮吸附脱附(比表面积及孔结构分析)等对氧化铝/碳纳米管复合材料进行表征，结果表明:未经聚乙烯醇改性的碳纳米管，氧化铝与碳纳米管相互分离;经聚乙烯醇改性的碳纳米管，氧化铝与碳纳米管结合良好。经聚乙烯醇改性的碳纳米管表面均匀覆盖一层聚乙烯醇膜，通过聚乙烯醇的吸附作用， Al(OH)₃沉积在碳纳米管表面形成一层连续的覆盖层。     

K_2CO_3活化制备花椒籽废渣的活性炭及其对对硝基苯酚的吸附性能

采用花椒籽废渣(RPS)为原料,K_2CO_3为活化剂制备了花椒籽废渣活性炭(KAC),以期实现农业废弃物的再利用。采用傅里叶变换红外光谱仪(FTIR)、扫描电子显微镜(SEM)、热重分析仪(TGA)、能量散射光谱(EDS)、X射线衍射仪(XRD)和气体吸附法等技术手段对其进行表征。分析了浸渍比(m(K_2CO_3)∶m(RPS))、浸渍时间、活化温度和活化时间对制备花椒籽废渣活性炭的影响,并且测试了花椒籽废渣活性炭对对硝基苯酚的吸附行为。研究结果表明,在浸渍比为0.8,浸渍时间为12 h,活化温度为550℃,活化时间为60min的条件下,活性炭的产率为29.3%,比表面积为1210 m~2/g,碘值为1002 mg/g,对亚甲基蓝的平衡吸附容量为362 mg/g,灰分为2.2%,水分为6.6%。对对硝基苯酚的吸附性能研究表明,293 K,pH=8.0,吸附180min后可达到吸附平衡,对硝基苯酚的吸附容量为406 mg/g,吸附可用Langmuir等温方程较好模拟,吸附为自发的放热过程。动力学研究表明该吸附符合准二级动力学模型。K_2CO_3活化法制备花椒籽废渣活性炭原料廉价,工艺简单,制得的活性炭吸附性能优异,具有较好的应用前景。     

Competitive Adsorption of Chloroform and Iron Ion onto Activated Carbon Fiber

Chloroform in tap water has been a significant problem because it may be a carcinogenic substituent. Iron ion exists in tap water because of dissolution from iron water pipes. Iron ions in tap water cause discoloration and a bad odor. The isotherms of chloroform and iron ion adsorption onto activated carbon fibers in a single solution (chloroform or iron ion) and in a binary mixture solution (chloroform and iron ion) were investigated to estimate the competitiveness between chloroform and iron ions. The amount of adsorbed iron ions increased with increasing pore volume of the activated carbon fibers, while that of chloroform decreased. The amount of chloroform adsorbed onto the activated carbon fibers in the binary mixture solution was greater than that in the single solution. These results indicate that the adsorption of chloroform and iron ion onto activated carbon fibers could be competitive.     

Structural Characterization and Property Study on the Activated Alumina-activated Carbon Composite Material

AlCl3,NH3·H2O,HNO3 and activated carbon were used as raw materials to prepare one new type of activated alumina-activated carbon composite material.The influence of heat treatment conditions on the structure and property of this material was discussed;The microstructures of the composite material were characterized by XRD,SEM,BET techniques;and its formaldehyde adsorption characteristic was also tested.The results showed that the optimal heat treatment temperature of the activated alumina-activated carbon composite material was 450 ℃,iodine adsorption value was 441.40 mg/g,compressive strength was 44 N,specific surface area was 360.07 m2/g,average pore size was 2.91 nm,and pore volume was 0.26 m3/g.According to the BET pore size distribution diagram,the composite material has dual-pore size distribution structure,the micro-pore distributes in the range of 0.6-1.7 nm,and the meso-pore in the range of 3.0-8.0 nm.The formaldehyde adsorption effect of the activated alumina-activated carbon composite material was excellent,much better than that of the pure activated carbon or activated alumina,and its saturated adsorption capacity was 284.19 mg/g.