STUDIES ON THE DYNAMIC COMPETITIVE ADSORPTION OF ORGANIC VAPORS ON THE ACTIVATED CARBON FIBERS ACTIVATED WITH PHOSPHORIC ACID

The dynamic competititve adsorption behaviors of different binary organic vapor mixtures on ACF-Ps under different operation conditons were investigated by gas chromatography in this paper,The studied mixtrues included benzene/toluene,toluene/xylene,benzene/isopropylbenzene ethly acetate/toluene and benzene/ethyl acetate.Experimental results show that various ACF-Ps,as with ACF-W,can remove both vapors in binary vapor mixtures with over 99% of removal efficiency before the breakthrough point of the more weakly adsorbed vapor,In dynamic competitive adsorption,the more weakly weakle adsorbed vapor noe only penetrates early,but also will be displaced and desorbed consequently by stronger adsorbate and therefore produces a rolling up in the breakthrough curve,The ACF-Ps prepared at different temperatuers have somewhat different adsorption selectivity,The feed concentration ratio of vapros,the length/diameter ratio and the thick of bed have effect on competitive adsorption.The competitive adsorption ability of a vapor is mainly related to its boiling point.Usually,the higher the boiling point ,the stronger the vapor adsorbed on ACF-P.     

ADSORPTION OF DYES ON ACTIVATED CARBON FIBERS

The adsorption behavior of dyes on a variety of sisal based activated carbon fibers (SACF) has been studied in this paper. The results show that this kind of ACF has excellent adsorption capacities for some organic (dye) molecules.SACF can remove nearly all methylene blue,crystal violet,bromophenol blue and Eriochrome blue black R from water after static adsorption for 24h. at 30℃. The adsorption amounts can reach more than 400mg/g when adding 50 mg SACF into 50 ml dye solution.Under the same conditions,the adsorption amounts of xylenol orange fluorescein and Eriochrome black T wree lower.On the other hand,the adsorption amounts change along with the characteristics of adsorbents.The SACFs activated above 840℃,which have higher specific surface areas and wider pore radii,have higher adsorption amounts for the dyes.The researching results also show that the adsorption rates of dyes onto SACFs decrease by the order of methylene blue,Eriochrome blue black R and crystal violet.     

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。     

磷酸活化粘胶基活性炭纤维的碳化活化机理

采用热重分析仪、红外光谱仪、X－射线衍射仪、核磁共振仪、X－射线光电子能谱仪及吸附仪等手段对磷酸浸渍粘胶纤维的碳化活性过程进行研究,实验结果表明：磷酸促进纤维素脱水,加上磷酸的阻及交联作用降低了纤维的大量裂解和碎片的逸散,使纤维的碳残留率提高。纤维素与浸渍的磷酸部分生成磷酸酯键,但它们在160℃以上逐渐分解。纤维上残留少量偏磷酸类化合物。同时纤维素基体脱水生成羰基和共轭双键,之后不断芳构化堆叠成为类石墨微晶。磷酸致孔的机理主要是磷酸珠粒的阻碍造成类石墨微晶发展不完善,堆叠时发生扭曲或形成缺陷。磷与纤维分子的酯化对微孔的生成有影响。     

活性炭纤维对氙的动态吸附性能研究

采用动态吸附实验装置，研究了吸附温度、原料气浓度和原料气流量对活性炭纤维动态吸附氙性能的影响。结果表明：在低温条件下（≤273K)，随着温度的升高，活性炭纤维对氙的平衡吸附量明显下降／同时，活性炭纤维对氙的平衡吸附量分别随着原料气浓度及原料气流量的增大而增大。     

ADSORPTION OF DYES ON ACTIVATED CARBON FIBERS

1.INTRODUCTIONDyewastewaterisakindofseriouspollutionsource.InthetraditionaltreatmentmethodsfordyewastewatergenerallytherearefourapproachesincludingelectricchargeneutraliZationofgelparticles,complexation(chelatation),redoxreaction,andbiochemicalcoagulationII~31.Recently,dyewastewaterhasbecomemoreconcentrated,moredifficulttodegradedbiochemically,andmorepoisonous,whichbringsaboutagreatchallengeforwatertreatment.AlthoughtheCOD(chemicaloxygendemand)mayfitthequalitystandardofwastewaterdischar…     

活性碳纤维吸附的研究Ⅰ-不同工艺制备的活性碳纤维的性能比较

本文比较研究了五种不同工艺制备的活性碳纤维（ACF）的产率、比表面积、孔结构、对有机溶剂蒸汽的吸附和脱附性能、对水溶液中亚甲基兰、苯酚和碘的吸附性能以及它们的热稳定性。实验结果表明，水蒸气活化的ACF比化学活化的ACF有更大的比表面积，但前者产品产率较低而后者很高；不论水蒸气活化还是化学活化的ACF，它们对有机溶剂饱和蒸汽的吸附量都较高，脱附和再吸附的性能也都较好，对水溶液中的苯酚都有较好的吸附能力，但化学活化的ACF对亚甲基兰的吸附量显著小于水蒸气活化的ACF，同时磷酸活化的ACF-P对碘的吸附量也明显偏小；除了用KOH活化的ACF外，其它ACF都有很好的热稳定性。     

沥青基活性炭纤维复合活化工艺的研究

以沥青基炭纤维为原料，研究了用铵盐作为化学活化剂对其进行浸渍预处理，然后采用（H2O＋CO2）活化的方法制备活性炭纤维，讨论了工艺条件对活性炭纤维性能的影响并通过光电子能谱XPS探讨了活化过程中炭纤维表面官能团的变化。结果表明：采用这种物理和化学复合活化工艺，可以在较高得率下提高活性炭纤维比表面积。同时浸渍处理、H2O流量、活化温度和活化时间等工艺参数显著影响活性炭纤维的比表面积和得率，优化的工艺为：经铵盐浸渍6h，炭纤维在水蒸气与CO2流量比3：1的混合气氛中900℃活化30min。XPS研究表明，活化后炭纤维表面的含氧官能团C－O明显减少，铵盐浸渍未能增加活性炭纤维表面的含氮基团。     

活性炭纤维对铂离子的还原吸附特征

利用不同的活化工艺,制备了水蒸汽活化和磷酸或氯化锌活化活性炭纤维,并借助扫描电镜(SEM)、X-射线衍射(XRD)和光电子能谱(XPS)等技术,研究了这些活性炭纤维对铂的还原吸附特征。结果表明,各活性炭纤维均能还原吸附铂离子,吸附容量为30mgPt/gC至90mgPt/gC之间。依据活性炭纤维种类的不同,还原吸附的铂呈粒状或放射性簇状存在于活性炭纤维表面,铂颗粒的粒径为几十nm至1μm之间。对纤维表面铂的XRD分析表明,还原吸附的铂呈无定型结构,但经过400℃高温处理后,颗粒转化为金属铂结晶形态。还原吸附铂后,活性炭纤维表面的含氧基团相应增加,显示其表面被氧化为羟基和羰基。     

活性炭纤维的微孔结构水吸附

测定了两种活性炭纤维（ACF）的氮气、水吸附等温线和XPS,研究了ACF的微孔结构和表面性质,用αs图分析氮吸附等温线获得了ACF的比表面积、微孔容量和微孔径。XPS表明在ACF表面存在多种不同结合状态的氧。水在ACF上的吸附等温线呈V型,具有很大的脱附滞后环。水通过与ACF表面的氧形成氢键发生吸附。ACF表面的初始吸附点多,则在低、中压时的水吸附量就大。     

改性活性炭纤维吸附二甲胺水溶液的研究

采用气相氧化法制备改性ACF,以二甲胺水溶液为吸附对象,在静态吸附条件下研究了吸附时间、温度、ACF用量对吸附效果的影响,获得了吸附等温线;在动态吸附条件下测定了动态穿透曲线,并研究了ACF的再生方法。在ACF优化用量0.6g/100mL溶液条件下,对初始浓度256mg/L二甲胺溶液的吸附率为85%;吸附饱和的ACF用5%盐酸溶液进行再生时,再生率接近100%。     

活性碳纤维对银离子还原吸附能力的改进

活性碳纤维不仅对有机物有高的吸附容量,对贵金属离子也具有强的还原吸附能力,可将Pd(Ⅱ）,Ag（Ⅰ）,Au（Ⅲ）等离子还原为金属单质。因而可用于提取矿液或加收废液中的贵金属。由此,提高或改善贵金属在活性碳纤维上的还原吸附容量或分布形成,显得非常重要。本文研究了活性碳纤维制备条件、表面氧化改性、以有负载有机物等对活性碳纤维还原能力的影响。结果表明,（1）制备条件对剑麻基活性碳纤维的还原能力有很大的影响。用H3PO4或ZnCl2活化的活性碳纤维对银离子具有更高的还原吸附容量,分别可达250和700mg/g,约为水蒸汽活化剑麻基活性碳纤维对银离子还原吸附容量的2倍和5倍。（2）过氧化氢、高锰酸钾、或硝酸等无机氧化剂对活性碳纤维进行表面改性,也能提高活性碳纤维的还原能力。结果表明,虽然改性活性碳纤维的比表面积和孔体积下降10-20%左右,但基表面含氧量及含氧基团的种类发生了改变。这些改性活性碳纤维对Ag(NH3)2^ 的还原吸附量大幅度提高,可达550mg/g以上。推断表面改性在活性碳纤维表面创造了更多有利于碱性条件下发生氧化还原的活性点。（3）在活性碳纤维表面负载适当的有机物如亚甲基蓝、苯胺或对硝基苯酚,也能显著提高活性碳纤维对Ag(NH3)2^ 的还原吸附能力。     

活性炭纤维对挥发性有机物的吸附及其等温线的拟合

空气中挥发性有机化合物（VOC）严重危害人的身体健康,因而研究VOC的去除具有重要意义。本文研究了不同比表面积粘胶基活性炭纤维（ACF）对低浓度VOC,丁酮和苯的吸附,并用Freundilch方程和DR方程对吸附等温线进行了拟合。结果表明：当丁酮的浓度高于100ppm时,比表面积高的ACF吸附容量高;当浓度低于100ppm时,情形正好相反。在实验浓度范围,较高比表面积的活性炭纤维对苯的吸附表现出了较高的吸附容量。Freundlich方程和DR方程能很好地拟合吸附等温线。     

STUDIES ON THE CATALYTIC REACTION OF NITROGEN OXIDE ON METAL MODIFIED ACTIVATED CARBON FIBERS

The catalytic reaction of NO with CO and decomposition of NO over metal modified ACFs were investigated and compared with other carriers supported catalysts. It is demonstrated that Pd/ACF and Pd/Cu/ACF have high catalytic activity for the reaction of NO/CO, while Pt/ACE. Pt/Cu/ACF and Co/Cu/ACF have very low catalytic activity in similar circumstance. Pd-modified ACF possesses high catalytic decomposition of NO at 300℃. Pd/CB and Pd/GAC present good catalytic decomposition abifity for NO only at low [lowrate. Pd/G Pd/ZMS and Pd/A however, do not show any catalytic activity for NO decomposition even at 400 ℃. Catalytic temperature, NO flowrate and loading of metal components affect the decomposition rate of NO. The coexistence of Cu with Pd on Cu/Pd/ACF leads to crystalline of palladium to more unperfected so as to that increase the catalytic activity.     

STUDIES ON THE CATALYTIC REACTION OF NITROGEN OXIDE ON METAL MODIFIED ACTIVATED CARBON FIBERS

1.INTRODUCTIONNitrogenmonoxide(NO)producedduringthecombustionprocessesisoneofthemostseriouspollutants,whichproducestownsmogandcausesotherseriousworldecologicalproblems.Inrecentyears,scientistspaidgreatattentionstocontrolandremovethiskindofpollutantbydifferenttechniques.Amongthem,catalytictechnologiesareattractivebecauseoftheirlowcostandhighefficiency[1].Nowadays,theNOismainlytreatedbycatalyticreductionwithreducingagentssuchasammoniaandsurphurdioxideandsoonovermetal-basedcatalysts.Thecar…     

STUDIES ON THE CHEMICAL STRUCTURES OFACTIVATED CARBON FIBERS BY SOLID STATE NMR

1INTRODUCTIONAsweknoW,theinvestigationofactivatedcarbonfibers(ACFs)hasbecomeaninterestingsubjectincarbonfieldbecauseACFspossessnovelstructures,goodadsorptionabilityandoutstandingoxjdation-reductionpropertyl'].ByuseofsomemoderntechniquessuchasXPS,FTIR,Xosandetc.,peoplehavestUdiedthestructUresofACFsandobtainedsomeinterestingresultS12-].However,therearestillsomelimitsforusingabovetechniquetostudythestructllresofACFs.Forexample,theXPSisonlyusedtostudythebindingstateofatomsonthesurf…     

STUDIES ON THE PREPARATION OF ZINC-CONTAINING ACTIVATED CARBON FIBERS AND THEIR ANTIBACTERIAL ACTIVITY

1. INTRODUCTION Microbial pollution will bring about various problems in industry and other vital fields, such as causing decomposing of materials, harming people抯 health. In order to reduce these problems, new antibacterial materials have been demanded. Recently, much attention has been paid to inorganic materials including zinc oxide [1~4]. These inorganic antibacterial materials are now substituting for organic materials to avoid releasing noxious organic molecules harmful to humans;…     

STUDIES ON THE PREPARATION OF ZINC-CONTAINING ACTIVATED CARBON FIBERS AND THEIR ANTIBACTERIAL ACTIVITY

Several kinds of activated carbon fibers, using sisal fiber as precursors, were preparedwith steam activation or with ZnCl2 activation. Zinc or its compounds were dispersed in them. Theantibacterial activities of these activated carbon fibers were determined and compared. The researchresults showed that these sisal based activated carbon fibers supporting zinc have strongerantibacterial activity against Escherichia coli and S. aureus. The antibacterial activity is related tothe precursors, the pyrolysis temperature, and the zinc content. In addition, small quantity of silversupported on zinc-containing ACFs will greatly enhance the antibacterial activity of ACFs.     

STUDIES ON THE CHEMICAL STRUCTURES OF ACTIVATED CARBON FIBERS BY SOLID STATE NMR

The solid state C13-NMR spectra of different ACFs from various precursor fibers were recorded in this paper,The effects of activation conditions on chemical structures of ACFs,as well as the changes of chemical structures during carbonization and redox reaction were inverstigated by NMR technique,At same time,the soild state P31-NMR spectra of ACFS are studied.The C13-NMR spectra of ACFs can be divided into six bands that are assigned to methyl and methylene groups,hydroxyl and ether groups.acetal (or methylenedioxy) carbon,graphite-like aromatic carbon structure,phenol,and quinone groups,respectively.Only phosphorous pentoxide exists on ACFs and CFs.Moreover,most of them are stuck over the crystal face but not at the edge of graphite-like micro-crystal.The carbonization and activation conditions affect the C13-NMR spectra of ACFs.The experimental rsults indicate that the redox reaction of ACFs with oxidants greatly consumes C-H group.     

活性炭的表面含氧官能团及其对吸附影响的研究进展

对活性炭表面含氧官能团的种类,生成原因以及活性炭含氧官能团的定性定量分析方法进行了综述。含氧官能团改变了活性炭的表面性质和表面行为,导致活性炭对金属离子和有机物的吸附性能发生变化,介绍了吸附金属离子和有机物时含氧官能团参与的作用机理,并对含氧官能团影响的研究提出了一些建议。