用锥形分层活性炭柱吸附去除对氯苯酚(英文)

The feasibility of adsorptive removal of single component organic compound(para-chlorophenol) by Calgon Filtrasorb 400(F400) carbon was investigated.The Redlich-Peterson equation was found to be the best fit model for describing the equilibrium relationship between the para-chlorophenol adsorption onto F400 carbon.Four adsorption columns with different column geometry and adsorbent particle stratification were used to examine the adsorption kinetics onto F400 carbons.The Bed Depth Service Time(BDST) model was applied and modified to analyse the performance of the columns and the effect of different operating variables.When combining the effects of adsorption efficiency and the associated pressure drop of each type of adsorption columns tested,the carbon stratified tapered column has been determined to be the most efficient engineering option for removing organics,in which the enhancement of the adsorbent bed in terms of longer breakthrough time and higher saturation percentage is the greatest amongst the four types of columns with reasonably small pressure drop across the fixed-bed column.     

竹制活性炭处理酸性染料废水吸附等温线模型的误差分析(英文)

High surface area activated carbons were produced by thermal activation of waste bamboo scaffolding with phosphoric acid.Single component equilibrium dye adsorption was conducted on the carbons produced and compared with a commercially available carbon.Two acid dyes with different molecular sizes,namely Acid Yellow 117(AY117) and Acid Blue 25(AB25),were used to evaluate the adsorption capacity of the produced carbons.It was found that the dye with smaller molecular size,AB 25,was readily adsorbed onto the produced carbon,nearly three times higher than a commercially available carbon,while the larger size dye,AY117,showed little adsorption.The experimental data were analyzed using isotherm equations including Langmuir,Freundlich,Tempkin,Toth,Redlich-Peterson and Sips equations.The equilibrium data were then analyzed using five different non-linear error analysis methods.     

活性炭纤维布吸附与电热脱附挥发性有机化合物研究进展(英文)

A general research program,focusing on activated carbon fiber cloths(ACFC) and felt for environmental protection was performed.The objectives were multiple:(i) a better understanding of the adsorption mechanisms of these kinds of materials;(ii) the specification and optimization of new processes using these adsorbents;(iii) the modeling of the adsorption of organic pollutants using both the usual and original approaches;(iv) applications of ACFC in industrial processes.The general question was:how can activated carbon fiber cloths and felts be used in air treatment processes for the protection of environment.In order to provide an answer,different approaches were adopted.The materials(ACFC) were characterized in terms of macro structure and internal porosity.Specific studies were performed to get the air flow pattern through the fabrics.Head loss data were generated and modeled as a function of air velocity.The performances of ACF to remove volatile organic compounds(VOCs) were approached with the adsorption isotherms and breakthrough curves in various operating conditions.Regeneration by Joule effect shows a homogenous heating of adsorber modules with rolled or pleated layers.Examples of industrial developments were presented showing an interesting technology for the removal of VOCs,such as dichloromethane,benzene,isopropyl alcohol and toluene,alone or in a complex mixture.     

正磷酸活化木质素吸附Cr(Ⅵ)的固定床实验和模型(英文)

The advantage of using an available and abundant residual biomass,such as lignin,as a raw material for activated carbons is that it provides additional economical interest to the technical studies.In the current investigation,a more complete understanding of adsorption of Cr(VI) from aqueous systems onto H3PO4-acid activated lignin has been achieved via microcolumns,which were operated under various process conditions.The practice of using microcolumn is appropriate for defining the adsorption parameters and for screening a large number of potential adsorbents.The effects of solution pH(2-8),initial metal ion concentration(0.483-1.981 mmol·L-1),flow rate(1.0-3.1 cm3·min-1),ionic strength(0.01-0.30 mmol·L-1) and adsorbent mass(0.11-0.465 g) on Cr(VI) adsorption were studied by assessing the microcolumn breakthrough curve.The microcolumn data were fitted by the Thomas model,the modified Dose model and the BDST model.As expected,the adsorption capacity increased with initial Cr(VI) concentration.High linear flow rates,pH values and ionic strength led to early breakthrough of Cr(VI).The model constants obtained in this study can be used for the design of pilot scale adsorption process.     

气相有机化合物在改性TiO2/AC复合光催化剂上的光催化降解动力学（英文）

This study is focused on the kinetic characteristics of photocatalytic degradation of gaseous organic compounds on modified titanium dioxide/activated carbon composite photocatalyst(MTA).The MTA,which co-doping with iron(Fe) and nitrogen(N),was synthesized by a sol-gel method,and its photocatalytic performance was investigated under different reaction conditions.The experimental data obtained were tested by the zero,first and second order kinetic model,and the factors affecting the kinetic model were analyzed.It was clearly demonstrated that the experimental data of toluene and acetone on MTA fit quite well with second order kinetic model equation,but the experimental data of formaldehyde fits well with zero order kinetic model equation.     

硝酸浓度对橄榄石基活性炭特性的影响(英文)

In this work we investigated the effect of nitric acid concentration on the pore structure, surface chemistry and liquid phase adsorption of olive stone based activated carbon prepared by mixing process using phosphoric acid and steam as activating agents. Chemicals and textural characterization show that the increase of HNO3 concentration increases considerably the total acidic groups but decreases specific surface area and pore volume. The study of adsorption in aqueous solutions of two organics, phenol and methylene blue, on raw and oxidized activated carbon indicates that the treatment of mixed activated carbon with different concentrations of nitric acid improves the adsorbent capacity for methylene blue at HNO3 concentrations less or equal to 2 mol·L 1, while it has a negative effect on phenol adsorption.     

含酚废水处理的吸附和臭氧氧化动力学模型

A three phase fluidized bed reactor was used to investigate the combined effect of adsorption and oxidation for phenolic wastewater treatment.Aqueous solutions containing 10 mg·L 1of phenol and ozone were continuously fed co-currently as upward flow into the reactor at constant flow rate of 2 and 1 L·min1,respectively.The phenolic treatment results in seven cases were compared:(a)O3 only,(b)fresh granular activated carbon(GAC),(c) 1st reused GAC,(d)2nd reused GAC,(e)fresh GAC enhanced with O3,(f)1st reused GAC enhanced with O3,and (g)2nd reused GAC enhanced with O3.The phenolic wastewater was re-circulated through the reactor and its concentration was measured with respect to time.The experimental results revealed that the phenolic degradation using GAC enhanced with O3 provided the best result.The effect of adsorption by activated carbon was stronger than the effect of oxidation by ozone.Fresh GAC could adsorb phenol better than reused GAC.All cases of adsorption on GAC followed the Langmuir isotherm and displayed pseudo second order adsorption kinetics.Finally,a differential equation for the fluidized bed reactor model was used to describe the phenol concentration with respect to time for GAC enhanced with O3.The calculated results agree reasonably well with the experimental results.     

ZL50活性炭吸附烟气脱硫过程的内扩散机制及其动力学模型

为考察扩散在炭法烟气脱硫中的机制和规律,用基于扩散的表观吸附动力学模型对烟气中不同SO2体积分数时动态吸附中的扩散过程进行了模拟和扩散机制分析。结果表明,SO2在ZL50脱硫脱硝活性炭内的扩散系数在10-16~10-13m2·s-1的范围内,扩散可能以构型扩散为主。颗粒内扩散模型随SO2体积分数增大和吸附时间推移预测性能提高;这说明SO2体积分数增加和吸附时间推移使得努森扩散比重增大,构型扩散比重减小,导致SO2扩散阻力比在催化氧化反应中克服更多活化能能垒阻力增加快,使扩散阻力在扩散反应总阻力中的比重增加。吸附过程的一种可能机制是从吸附前期的表面反应控制过渡到后期的扩散与表面反应联合控制。     

用椰壳制活性炭吸附去除三价铋离子(英文)

In present study,we report the preparation of coconut shell activated carbon as adsorbent and its appli-cation for Bi(Ⅲ) removal from aqueous solutions.The developed adsorbent was characterized with scanning elec-tron microscope(SEM),Fourier Transform Infrared(FTIR),C,H,N,S analyzer,and BET surface area analyzer.The parameters examined include agitation time,initial concentration of Bi(Ⅲ),adsorbent dose and temperature.The maximum adsorption of Bi(Ⅲ)(98.72%) was observed at 250 mg·L-1 of Bi(Ⅲ) and adsorbent dose of 0.7 g when agitation was at 160 r·min-1 for 240 min at(299±2) K.The thermodynamic parameters such as Gibb’s free energy(△Gθ),enthalpy(△Hθ) and entropy(△Sθ) were evaluated.For the isotherm models applied to adsorption study,the Langmuir isotherm model fits better than the Freundlich isotherm.The maximum adsorption capacity from the Langmuir isotherm was 54.35 mg?g?1 of Bi(Ⅲ).The kinetic study of the adsorption shows that the pseudo second order model is more appropriate than the pseudo first order model.The result shows that,coconut shell ac-tivated carbon is an effective adsorbent to remove Bi(Ⅲ) from aqueous solutions with good adsorption capacity.     

改性活性碳纤维对苯胺吸附特性分析

开展了等离子体改性活性碳纤维对苯胺吸附性能的理论和实验研究。通过改变等离子体改性功率和改性时间,探寻最佳改性条件;采用BET、XPS、FTIR、热重测试对改性前后活性碳纤维理化特性进行了表征分析。结果表明,在等离子改性功率为22W,时间为3min时为最佳改性条件;改性后的活性碳纤维对水溶液中苯胺的去除率可达79.3%,去除率提高了8%。微观上等离子体改性使得活性碳纤维表面含氧官能团含量增加,增强对溶液中苯胺的吸附效果。吸附实验结果表明,改性前后活性碳纤维对苯胺的吸附在溶液pH为6时,吸附效果最佳;但达到同一去除率时改性活性碳纤维的速度更快,并且平衡吸附容量也更大。采用准一级和准二级动力学模型对该吸附过程进行描述,其改性前后均用准二级动力学拟合效果更好,表明活性碳纤维结构的特殊性使其对苯胺的吸附以化学吸附为主。活性碳纤维的等离子体改性提高了其对水溶液中苯胺的吸附速度和容量,增强去除效果降低了苯胺对环境的危害。     

褐煤活性炭吸附苯酚的研究

The feasibility and adsorption effect of lignite activated carbon for phenol removal from aqueous solutions were evaluated and investigated. A series of tests were performed to look into the influence of various experimental parameters such as contact time, initial phenol concentration, temperature, and pH value on the adsorption of phenol by lignite activated carbon. The experimental data were fitted well with the pseudo-second-order kinetic model. The adsorption is an endothermic process and conforms to Freundlich thermodynamic model. The results indicate that the lignite activated carbon is suitable to be used as an adsorbent material for adsorption of phenol from aqueous solutions.     

Granular activated carbon adsorption process for removing trichloroethylene from groundwater

Batch adsorption capacity experiments and continuous flow breakthrough experiments were conducted to compare the effectiveness of seven granular activated carbons (GACs) in removing trichloroethylene (TCE) from groundwater. The order of GACs' adsorptive capacities for TCE was the same as their phenol numbers (indicator for <1 nm micropores). A small amount of methanol (0.05% v/v) did not affect the pure water TCE capacities, which were notably reduced by the small organic constituents of tap water. The breakthrough results show low utilization of the available adsorptive capacity due to both slow mass transport and the need to achieve a high degree of TCE removal, and that the serial bed mode of treatment is cost effective because a very high capacity utilization can be attained. The low‐cost, environmental friendly bamboo GAC is attractive as its competitive TCE capacity was readily used in actual treatment because of its favorable pore structure. © 2010 American Institute of Chemical Engineers AIChE J, 2011     

活性炭吸附法脱硫实验研究和工业性应用

研究了周期性水洗涤脱附对活性炭脱硫性能的影响。经过 4次吸附、脱附循环后 ,活性炭的动态吸附性能和脱附性能达到平衡。活性炭颗粒越小 ,床层穿透时间越长 ,脱硫效率越高。当进口SO2 质量分数为 3× 1 0 - 3时 ,活性炭脱硫效率达到96 %以上。工业性实验表明 ,采用水洗涤脱附 ,活性炭脱硫效率稳定。燃煤烟气工业性实验排放烟气SO2 质量分数小于 9×1 0 - 5,脱硫效率达到 93 %。     

改性球形活性炭对氨气吸附性能的研究

研究了不同金属盐溶液浸渍改性的球形活性炭对氨气的吸附性能以及同种浸渍剂的最佳浸渍比。采用扫描电镜、透射电镜、X射线衍射仪、康塔吸附仪探究了不同浸渍比对浸渍炭样品的表面形貌、物相结构及孔径分布的影响。通过固定床吸附装置对基炭和浸渍炭进行了氨气吸附性能的研究。结果表明：浸渍剂种类对氨气吸附效果有很大影响, 同等浸渍条件下, 氯化钴浸渍的活性炭具有最优氨气吸附效果, 氯化钴浸渍比为50%的样品对氨气的吸附量最高, 可达54.05 mg/mL, 为基炭的37倍。对吸附氨气后样品的物化性质进行分析以及程序升温脱附表征, 结果表明氯化钴与氨气反应生成了[Co（NH₃）₆]Cl₃。     

铜铁基改性活性炭对烟气中二价汞的吸附

随着工业的发展,环境问题日趋严重,而二价汞污染作为环境问题之一受到越来越多的关注。本文采用过体积浸渍法制备了铜基和铁基[CuCl₂,FeCl₃,Cu （NO₃）₂]改性的活性炭,考察了不同浓度以及煅烧温度制备的改性活性炭对模拟烟气中二价汞（HgCl₂）脱除性能的影响。通过吸附穿透实验的对比研究得出,无论是铜基或铁基改性的活性炭都对含氯化汞烟气有很好的吸附效果,并且300℃焙烧的0.01mol/L的氯化铜改性活性炭是深度脱除含氯化汞烟气效果最好的改性活性炭,其吸附量达到了4.55mg/g。在此基础上,进一步利用了XRD、BET、XPS常用表征手段研究了改性前后活性炭的物理化学特性,证明了铜基、铁基改性活性炭吸附氯化汞都是物理吸附与化学吸附共同作用的结果,并给出了相应的解释,以期为后续的科学研究提供一定的思路。     

一种改进的LDF模型及其在活性炭吸附中的应用

以固相表面扩散模型为基础,研究了活性炭在不同吸附质浓度下单颗粒的吸附速率与吸附量之间的关系,以及颗粒内浓度分布随时间的变化过程。结合文献对LDF模型的假设,认为吸附初期对吸附剂颗粒内浓度分布做抛物线假设误差较大,吸附初期颗粒表面浓度分布梯度偏低,使得吸附速率降低,并提出了改进后的LDF模型,最后结合固相表面扩散模型和活性炭颗粒吸附SO₂固定床穿透实验曲线进行了验证。结果表明,采用改进后的LDF模型作为推动力方程的穿透曲线模型能够更加准确地描述实验过程。本文的研究结果能够为活性炭吸附过程提供理论依据和模型参考。     

活性炭对重金属离子的吸附研究

研究了活性炭分别对铅、镉、铜及锌离子的吸附作用,研究了pH值、温度及活性炭的投加量等因素对吸附效果的影响。结果表明,当pH〉5时对四种离子的去除率均达到98％以上,能达到很好的吸附。低温有利于吸附的进行。随着活性炭的增加．重金属离子的去除率增加．而且铜离子的活性炭最佳用量是0．3000g．铅、镉和锌的活性炭最佳用量均为1．000g。随着吸附时间的增加,去除率上升。铜、铅、镉和锌离子的吸附平衡时间分别为3．5h、1h、1．5h和1．5h。铜离子的吸附符合Langmuir等温模式,而锌、铅和镉离子的吸附符合Freundlich等温模式。     

浸渍法改性活性炭纤维吸附一氧化氮的研究

采用不同浓度的硝酸铁溶液在不同的处理温度和时间下,浸渍聚丙烯腈基活性炭纤维(PANACF), 用正交实验法分析影响改性PAN-ACF吸附一氧化氮转化率的主要因素。实验结果表明,浸渍液的初 始浓度是影响一氧化氮吸附转化率的主要因素。在初始浓度为0.1-0.14mol／L时,吸附转化率达到最大 值70％左右,吸附温度和吸附时间对吸附转化率影响不大。通过扫描电镜观察,铁离子不规则分布在PANACF 表面。     

有序介孔碳和活性炭对阿莫西林的吸附研究

阿莫西林是废水中一类典型的药品与个人护理品类新型有机污染物,会对周围环境和人体健康造成潜在威胁。以蔗糖为碳源、以SBA-15为模板制备有序介孔碳（OMC）。采用动态吸附法研究其对阿莫西林的吸附行为,并与常规吸附材料商用活性炭（GAC）作对比。探讨了废水中阿莫西林的初始浓度、温度及流速对动态吸附的影响。结果表明：在同等条件下,OMC的吸附能力远强于GAC,以OMC为吸附剂可有效去除废水中的阿莫西林类新型有机污染物。