中孔活性炭材料的研究进展

综述了国内外在中孔活性炭材料开发方面的研究进展。着重介绍了催化活化、界面活化、混合聚合物炭化、有机凝胶炭化、铸型炭化等孔径调控方法及其中孔形成机理。为控制活性炭材料孔径大小和分布，提高其中孔容积和吸附性能提供了参考。     

通过与热塑性树脂共热处理来改造活性炭的孔结构研究

三种具有不同比表面积的活性炭—椰壳基AC—C、粒状AC—P和竹基AC—B分别与四种热塑性前驱体（改性剂）—聚乙烯醇（PVA），羟基丙基纤维素（HPC），柠檬酸（CiA），含氟聚酰亚氨（FPI）混合后，在900℃热处理1h。通过氮气吸附法和扫描电镜对改性后活性炭的孔结构进行了表征。实验发现，热塑性树脂对活性炭AC—B的孔结构改性最显著；而另外三种改性剂PVA，HPC和CiA的改性结果使得AC—B的表面积降低，这是由于对其微孔结构改性效果不同所引起的：PVA可消除所有微孔，HPC可以有效消除极微孔，而CiA仅减少极微孔体积，但增加了超微孔体积。一方面，30％CiA的添加量，导致AC-B的外表面积增加了170％；另一方面，改性剂FPI通过增加极微孔，使其表面积增加达2倍之多。通过选择改性剂，能够改变活性炭基体中的微孔孔径分布，实际上是通过增加或减少其中的极微孔来实现。     

不同活化条件下制得粘胶基ACF的孔结构

将粘胶丝用前处理剂预处理后,在相同的碳化条件下,通过不同的活化时间及活化温度来制备活笥炭纤维,然后用英英张簧称ＢＥＴ重量法,测定出 比表面积和孔径分布及孔结构参数,实验结果表明,随着活化条件的改变,所制备的粘胶基ＡＣＦ的比表面积,孔径分布和孔结构参数也明显不同,但是它们都有相对较集中的孔径分布和辊的微孔比率。     

由CO2作活化剂制活性炭织物的孔结构和吸附性能研究

以ＣＯ２为活化剂,制备ＰＡＮ基活性炭织物。进行了孔结构的表征（氮吸附）、苯吸附及碘吸附实验。结果表明,用ＣＯ２为活化剂所得活性炭织物的比表面比用水蒸汽或ＫＯＨ等要低,前者产品的孔分布比后者窄。但当使用纯ＣＯ２时所得产品的孔分布比用普通ＣＯ２时为窄,大孔含量少     

活性炭吸附剂的孔结构表征

利用低温氮吸附法 ,对 6种不同来源的活性炭吸附剂的孔结构进行了表征。结果表明 :各种不同的活性炭吸附剂均具有较大的比表面积和发达的微孔 ;其中两种活性炭吸附性能更佳 ,作为吸附剂效果较好     

高温热处理对中孔较发达的沥青基球状活性炭孔结构的影响

本文研究了前热处理和后热处理对中孔较为发达的沥青基球状活性炭孔结构的影响。结果表明,热处理可以使沥青基球状活性炭的孔容及比表面积缩小,特别是前特处理还可以使沥青基球状活性炭的孔径分布及微孔与中孔的比例在一定的范围内变化,这就为沥青基球状活性炭的孔径控制提供了可能。     

高温热处理对中孔较发达的沥青基球状活性炭孔结构的影响

本文研究了前热处理和后热处理对中孔较为发达的沥青基球状活性炭孔结构的影响。结果表明,热处理可以使沥青基球状活性炭的孔容及比表面积缩小,特别是前热处理还可以使沥青基球状活性炭的孔径分布及微孔与中孔的比例在一定的范围内变化,这就为沥青基球状活性炭的孔径控制提供了可能     

由改性聚丙烯腈原丝制中孔活性炭纤维

为了满足活性炭纤维在医药，电子，催化及液相吸附领域的应用，中孔活性炭纤维的研制已成为多孔炭材料的发展方向之一，本文从纺制原丝出发，制得含非金属组份炭黑或石墨偻的特种聚丙烯腈原线，该原丝经常规水蒸汽活化后可得中孔率达５８％的活性炭纤维，本文还表征了其孔结构，测量了其气，液相吸附性能。     

磷酸活化碱木质素制备活性炭

以造纸黑液回收的碱木质素为前驱体,经磷酸活化制备低成本的木质素活性炭,对活性炭进行比表面积、孔结构及形貌的表征;考察活化温度、磷酸与碱木质素浸渍比、活化时间以及N2流量对活性炭产率及孔结构的影响。结果表明:磷酸活化碱木质素制备活性炭的产率都大于60%;在活化温度为550℃,磷酸与木质素浸渍比为1.5,活化时间3 h以及N2体积流量为75 m L/min时,活性炭比表面积达到1 139 m2/g;低成本的碱木质素是制备低成本活性炭的潜在的前驱体材料。     

活性炭孔结构调节:理论、方法与实践

活性炭的吸附性能主要由其孔结构和表面官能团决定,尤其是孔结构对活性炭的性能有时甚至有决定性的影响.因此,根据用途与应用领域对吸附剂性能的要求定向制备具有特定孔结构的活性炭的方法具有重大的意义.通过对活性炭制备过程中孔结构调控方法研究状况的评介,以期对深入理解孔结构对活性炭的意义、阐释孔结构调控机理和方法有所帮助,进而指导制备具有要求结构和性能活性炭的生产实践.     

Boron removal from aqueous solutions by activated carbon impregnated with salicylic acid

In this study, the removal of boric acid from aqueous solution by activated carbon impregnated with salicylic acid was studied in batch system. pH, adsorbent amount, initial boron concentration, temperature, shaking rate and salicylic acid film thickness were chosen as parameters. Boron removal efficiencies increased with increasing adsorbent amount, temperature and pH, decreasing initial boron concentration. As thickness of salicylic acid film on activated carbon becomes thin up to 0.088nm, the efficiency increased, and then, the efficiency decreased with becoming thinner than 0.088nm of salicylic acid film. Shaking rate was no effect on removal efficiency. In result, it was determined that the use of salicylic acid as an impregnant for activated carbon led to the increase of the amount of boron adsorbed. A lactone ring, being the most appropriate conformation, forms between boric acid and -COOH and -OH groups of salicylic acid.     

双电层电容器用中孔炭微球/活性炭复合电极的制备

采用水热法合成比表面积1850m2/g、粒径lμm的中孔炭微球(MCM);而后将所制MCM加入比表面积为3200m2/g的超级活性炭(HSAC)中制成用于双电层电容器的复合电极材料,并研究了该复合电极材料的电化学性能.结果表明:在比表面积为3200m2/g的HSAC中添加质量分数20%的MCM后,其颗粒接触内阻、离子扩散内阻明显降低;在6mol/L的KOH电解液体系中,在12A/g的电流密度下,其比电容仍能稳定在230F/g.而在同样的条件下,纯HSAC和纯MCM的比电容仅分别为190F/g和148F/g.复合电极在大电流下电化学性能的提高应归因于MCM合适的粒径、中孔结构及其较高的比表面积.     

Adsorptive removal of acrylonitrile by commercial grade activated carbon: kinetics, equilibrium and thermodynamics

The potential of activated carbons--powdered (PAC) and granular (GAC), for the adsorption of acrylonitrile (AN) at different initial AN concentrations (50相似文献   

聚苯乙烯基球形活性炭的制备及其对二苯并噻吩的吸附性能

通过水蒸气活化法制备了聚苯乙烯基球形活性炭,并研究了其对二苯并噻吩(DBT)的吸附性能.采用扫描电镜(SEM)、N2吸附、热重分析(TG)以及液相吸附试验考察了球形活性炭的结构特征.结果表明:以苯乙烯离子交换树脂为原料,通过水蒸气活化法,可以得到比表面积979m2/g～1672m2/g的球形活性炭.其中,BET比表面积和孔容随活化时间和水蒸气流量的增加而增大,而孔径小于0.7 nm的窄微孔却减小.球形活性炭对DBT的吸附量可达109.36mg/g,吸附量与比表面积和总孔容关系不大,而与小于0.7nm的窄微孔成正比.球形活性炭在对DBT的吸附过程中存在不可逆吸附.球形活性炭所含窄微孔的孔容越大,脱附所需要的温度越高,不可逆吸附量越大.     

高温热处理对活性炭纤维微孔及表面性能的影响

研究了1173K高温改性处理对沥青基活性炭纤维吸附性能、孔径分布、微孔结构和表面化学的影响。低温(77K)N2吸附结果表明热处理后活性炭纤维比表面积略有下降，通过密度函数理论解析活性炭纤维全孔范围的孔分布得出活性炭纤维表面孔径大于1．0nm的微孔明显减少，微孔孔径更加集中于0．5nm～1．0nm，从而提高了活性炭纤维的碘吸附值。X射线衍射分析表明活性炭纤维是乱层石墨结构，热处理使活性炭纤维类石墨微晶碳层面的层间距下降，X光电子能谱分析表明热处理后活性炭纤维表面的含氧官能团C=O和COOH的含量变化不大，而呈碱性酚羟基C—OH含量的明显下降使活性炭纤维表面碱性降低。     

CuO impregnated activated carbon for catalytic wet peroxide oxidation of phenol

This paper presents an original approach to the removal of phenol in synthetic wastewater by catalytic wet peroxide oxidation with copper binding activated carbon (CuAC) catalysts. The characteristics and oxidation performance of CuAC in the wet hydrogen peroxide catalytic oxidation of phenol were studied in a batch reactor at 80 °C. Complete conversion of the oxidant, hydrogen peroxide, was observed with CuAC catalyst in 20 min oxidation, and a highly efficient phenol removal and chemical oxygen demand (COD) abatement were achieved in the first 30 min. The good oxidation performance of CuAC catalyst was contributed to the activity enhancement of copper oxide, which was binding in the carbon matrix. It can be concluded that the efficiency of oxidation dominated by the residual H₂O₂ in this study. An over 90% COD removal was achieved by using the multiple-step addition in this catalytic oxidation.     

Using phenol–formaldehyde resin as carbon source to synthesize mesoporous carbons of different pore structures

In this research communication, we performed the phenol–formaldehyde (PF) resin as an alternative carbon source and various mesostructured silicas as the nano-templates to conveniently prepare the mesoporous carbons of high surface area (850–1500 m² g⁻¹), large pore size (2.0–22.0 nm) and great pore volume (0.65–1.15 cm³ g⁻¹). It was reasonably supposed that there exist interaction matching between the negative-charged silica surface of the silica template and PF resin. Therefore, the PF oligomers could be homogeneously adsorbed into the nanochannels or cages of the mesoporous silicas via an impregnation process. Because the thermosetting PF resin only requires a simple heat treatment process at 100 °C to form the cross-linked polymeric structure, the replication of the mesostructure of the mesoporous silica template could be readily achieved without adding any polymerization catalysts.     

Removal of nitroimidazole antibiotics from aqueous solution by adsorption/bioadsorption on activated carbon

The objective of the present study was to analyse the behaviour of activated carbon with different chemical and textural properties in nitroimidazole adsorption, also assessing the combined use of microorganisms and activated carbon in the removal of these compounds from waters and the influence of the chemical nature of the solution (pH and ionic strength) on the adsorption process. Results indicate that the adsorption of nitroimidazoles is largely determined by activated carbon chemical properties. Application of the Langmuir equation to the adsorption isotherms showed an elevated adsorption capacity (X_m = 1.04–2.04 mmol/g) for all contaminants studied. Solution pH and electrolyte concentration did not have a major effect on the adsorption of these compounds on activated carbon, confirming that the principal interactions involved in the adsorption of these compounds are non-electrostatic. Nitroimidazoles are not degraded by microorganisms used in the biological stage of a wastewater treatment plant. However, the presence of microorganisms during nitroimidazole adsorption increased their adsorption on the activated carbon, although it weakened interactions between the adsorbate and carbon surface. In dynamic regime, the adsorptive capacity of activated carbon was markedly higher in surface water and groundwater than in urban wastewaters.     

The dynamic adsorption characteristics of phenol by granular activated carbon

The objective of the present work is to determine the operating conditions of an activated carbon filter, based on the characteristics of breakthrough curves. For this we apply the technical developed by Mickaels for the ionic exchange and applied by Luchkis for the adsorption, and which is the mass transfer zone. To reach our goal, an evaluation of the operating conditions (height of the bed, flow and concentration of effluent) on the characteristics of the mass transfer zone was made and an explanation of the mechanism of adsorption was given. Thereafter a modeling of the experimental results was done.