共查询到19条相似文献,搜索用时 203 毫秒
1.
活性炭纤维的微孔结构水吸附 总被引:3,自引:0,他引:3
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。 相似文献
2.
研究了3种不同经表面积活性炭纤维(ACF)对气相低浓度三氯乙烯(TCE)的动态吸附。ACF的比表面积为600m^2/g、1400m^2/g和1600m^2/g,TCE的浓度范围为27mg/m^3-2725mg/m^3。结果表明,比表面积为1400m^2/g和1600m^2/g的ACF对TCE的吸附较好;10%穿透时间的对数与TCE匠对数呈线性关系;穿透时间随温度和湿度的增加而缩短;穿透曲线可以用经验公式拟合。拟合值和实测值吻合良好;ACF吸附是去除气相低浓度TCE的有效方法。 相似文献
3.
以核桃壳为原料,氢氧化钾作活化剂制备了高比表面积活性炭,使用苯基三甲氧基硅烷对其进行表面改性,得到苯基键合活性炭。通过氮气吸附法测定了活性炭的比表面积及孔隙结构,使用X射线光电子能谱表征测定了苯基键合活性炭的表面结构及碳元素含量。采用Langmuir热力学方程、Freundlich热力学方程、Lagergren准一级、准二级动力学方程及D-R方程对苯基键合活性炭对苯的吸附等温线进行了拟合。考察了温度和采气流速对吸附效率的影响。结果表明,苯基键合活性炭的孔隙主要为微孔,比表面积达2800 m~2·g~(-1);苯基键合活性炭对苯的吸附符合Langmuir等温吸附模型和Lagergren准一级动力学方程,饱和吸附量为713. 89 mg·g~(-1),苯的特征吸附能为23. 495 kJ·mol~(-1);增加温度或采气流速均使活性炭对苯的吸附量减少。 相似文献
4.
LIU Zi-hong QIU Jian-rong LIU Hao TAN Zeng-qiang YAN Zhi-qiang ZHANG Man-na ZENG Han-cai YANG Hui 《燃料化学学报》2012,40(1)
采用H2O2浸渍的方法对活性炭纤维(ACF)进行改性,并利用氮吸附等温线和XPS(X-ray photoelectron spectroscopy)的方法对ACF样品进行表征.通过实验测定改性前后ACF脱除VOC(甲苯作为VOC的代表物)的效果,同时考察二氧化硫( SO2)和一氧化氮(NO)对ACF脱除甲苯的影响.研究发现,双氧水浸渍改性对ACF的BET表面积和孔容没有影响,但使得ACF样品表面的含氧官能团含量大量增加.实验数据也表明,SO2和NO对VOC在ACF上的吸附具有抑制作用,且随着两者浓度的增加,抑制作用也增强.研究还发现,SO2和NO同时存在比单一的SO2或NO对VOC在ACF上吸附的抑制作用更为明显. 相似文献
5.
SO2和NO对ACF低温脱除模拟燃煤烟气中VOC的影响 总被引:1,自引:0,他引:1
采用H2O2浸渍的方法对活性炭纤维(ACF)进行改性,并利用氮吸附等温线和XPS(X-ray photoelectron spectroscopy)的方法对ACF样品进行表征。通过实验测定改性前后ACF脱除VOC(甲苯作为VOC的代表物)的效果,同时考察二氧化硫(SO2)和一氧化氮(NO)对ACF脱除甲苯的影响。研究发现,双氧水浸渍改性对ACF的BET表面积和孔容没有影响,但使得ACF样品表面的含氧官能团含量大量增加。实验数据也表明,SO2和NO对VOC在ACF上的吸附具有抑制作用,且随着两者浓度的增加,抑制作用也增强。 研究还发现,SO2和NO同时存在比单一的SO2或NO对VOC在ACF上吸附的抑制作用更为明显。 相似文献
6.
用密度函数理论和杜比宁方程研究活性炭纤维多段充填机理 总被引:12,自引:0,他引:12
本文运用密度函数理论(DFT)和杜比宁方程分别对活性炭纤维(ACF)的氮吸附等温线进行解析,经过两种解析结果的对比,验证了ACF上的多段充填机理,提出与各吸附段相对应的孔径范围,并讨论了各吸附段的吸附分压。在此基础上,比较了不同原料ACF的不同孔径结构对其多段吸附的决定作用。 相似文献
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吸附树脂和活性炭对气体中苯的吸附研究 总被引:2,自引:0,他引:2
采用了动态吸附实验方法研究了吸附树脂NDA-201和椰壳型活性炭C1对苯蒸汽的吸附行为.对吸附平衡数据采用Dubinill-Astakov方程进行了拟合分析,并根据吸附剂孔结构特征探讨了吸附机理.实验结果表明,两种吸附剂的苯吸附等温线存在交叉现象,对高浓度苯蒸汽吸附治理可采用NDA-201树脂,低浓度则采用椰壳型活性炭C1;Dubinin-Astakov方程能用来对两种吸附剂的等温线进行拟合,表明吸附剂的微孔区域对吸附起着重要作用.微孔体积计算值的比较和特征曲线叠合的程度说明了.Polanyi吸附势理论更适合于描述椰壳型活性炭C1对苯的吸附,这可能是由于椰壳型活性炭C1的孔分布集中于微孔区,而NDA-201树脂除了微孔外还有一定量的中孔和大孔. 相似文献
10.
PAN基活性炭纤维的表面及其孔隙结构解析 总被引:5,自引:0,他引:5
通过氮吸附等温线、X射线光电子能谱以及扫描电子显微镜(SEM)对聚丙烯腈(PAN-Polyacrylonitrile)-基活性炭纤维(ACF-Activated Carbon Fiber)的表面和孔隙结构进行了分析,结果表明吸附测量可以提供有关碳质吸附剂的孔结构复杂性;通过XPS对PAN基ACF的表面官能团的种类及含量进行了表征,由SEM对PAN基ACF的表面以及断面的孔隙结构进行了直接观察,提供了有关孔隙结构的直接证据。 相似文献
11.
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 相似文献
12.
使用盐酸对吸附剂活性炭纤维(activated carbon fiber,ACF)进行改性,通过SEM、BET和FTIR对改性前后的ACF形貌及结构进行系统表征发现,改性后ACF较改性前表面杂质减少且沟壑更加明显,比表面积提高22%,微孔体积增加5%,含氧官能团(C-O和C=O)明显增多. 以水中重金属离子(Zn(II)及Cr(VI))和抗生素磺胺甲恶唑(Sulfamethoxazole,SMX)为目标污染物,研究改性后ACF对目标污染物的吸附(静吸附和电吸附)性能,考察了浓度、pH、外加电压对吸附的影响. 结果表明,ACF用量为5 g,电压为1.2 V,Zn(II)、Cr(VI)及SMX浓度均为10 mg·L-1,Zn(II)溶液pH为5时,ACF吸附水中Zn(II)的最大吸附量为9.25 mg·g-1,是静吸附条件的2.15倍;Cr(VI)溶液pH为4时,ACF吸附Cr(VI)的最大吸附量为8.86 mg·g-1,是静吸附条件的1.96倍;SMX溶液pH为6时,ACF吸附SMX的最大吸附量为8.32 mg·g-1,是静吸附条件的1.84倍. ACF吸附Zn(II)、Cr(VI)及SMX的动力学曲线均符合准二级动力学模型,吸附过程为化学吸附. Freundlich等温模型能更好地描述ACF对Zn(II)、Cr(VI)及SMX的吸附特性,其吸附形式为多分子层吸附. ACF通过电极反接方式进行循环再生,脱附速率快且脱附效果明显,经4次循环再生后,ACF对Zn(II)、Cr(VI)及SMX的去除率均在90%以上. 相似文献
13.
The present study analyses the preparation of activated carbon fibres (ACFs) by the so-called “physical” activation method
with steam or carbon dioxide and their application for benzene and toluene adsorption at low concentration (200 ppmv). ACFs
have been scarcely studied for the adsorption of these pollutants at low concentration in gaseous phase, despite their interesting
features regarding adsorption kinetics, bed pressure drop, possibility of conformation and others. Our results have shown
that the preparation method used is suitable to produce ACFs with high adsorption capacities for benzene and toluene at the
low concentration used. The fibre morphology of the ACFs does not enhance their performance, which results to be similar to
other non-fibrous activated carbons such as granular, pellets and powders. Such good performance of the ACFs, leading to benzene
and toluene adsorption capacities as large as 31 g benzene/100 g ACF or 53 g toluene/100 g ACF, can be explained due to their
large volume of narrow micropores (<0.7 nm) developed upon activation and their low content in surface oxygen groups. Our
results have also shown very good agreement between the adsorption results derived from dynamic adsorption experiments and
from adsorption isotherms. As the relative pressure of the organic compound increases the corresponding fraction of narrow
micropore volumes filled by benzene and toluene increases. For a given low and comparable relative pressure, toluene always
occupies a larger fraction of narrow micropores than benzene. 相似文献
14.
Du ChangMing Huang DongWei Li HongXia Xiao MuDan Wang Kui Zhang Lu Li ZhiYi Chen TengFei Mo JianMin Gao Dong Huang YuHao Liu ShangKun Yu Liao Zhang ChuangRong 《Plasma Chemistry and Plasma Processing》2013,33(1):65-82
As a main composition of dye wastewater, organic pollutant which has a negative effect on the environment can be effectively removed by active carbon adsorption. In the present work, activated carbon fiber (ACF) was modified by a novel modification technology, gilding arc discharge, while its adsorption capacity was studied with the acid orange II (AO II) solution selected as the target wastewater. Several factors, such as air flow rate, distance between samples and the discharge area, pH of the solution and plasma treating time, were investigated with respect to their effects on properties of the plasma-treated ACF, in terms of texture characteristic, surface chemical compositions and adsorption capacities. The results showed that the specific surface area and pore volume of ACF decreased after the plasma treatment, while the amounts of oxygen-containing functional groups on the surface of ACF increased compared with the raw ACF. Moreover, it was observed that the adsorption capacity of the modified ACF was improved by nearly 20.9 %, which was beneficial to the industrial application. 相似文献
15.
In this study, activated carbon fibers (ACFs) were produced by an oxyfluorination treatment to enhance the capacity of ammonia gas removal. The introduction of polar groups, such as CF, CO, and COOH, on the ACFs was confirmed by a XPS analysis, and N2/77 K adsorption isotherm characteristics including specific surface area and total and micropore volumes were studied by the BET and t-plot methods. The ammonia-removal efficiency was confirmed by a gas-detecting tube technique. As a result, the specific surface area and micropore volume of ACFs were slightly destroyed as the surface treatment time was increased. However, the oxyfluorinated ACFs led to an increase of fluorine and oxygen-containing polar functional groups in ACF surfaces, resulting in an increase in the ammonia-removal efficiency of the ACFs produced. 相似文献
16.
Haiqin Rong Zhenyu Liu Qilin Wu Ding Pan Jingtang Zheng 《Cellulose (London, England)》2010,17(1):205-214
We impregnated Rayon-based activated carbon fibers (ACFs) by p-aminobenzoic acid (PABA) and systematically investigated their porous structure, surface chemistry, and formaldehyde removal
behavior. Using standard nitrogen adsorption analysis, we found that the specific surface area, the micropore volume, and
the total pore volume decreased with increasing concentration of PABA. Through elemental analysis and X-ray photoelectron
spectroscopy, it was found that some nitrogen-containing functional groups presented on the surface of modified Rayon ACFs.
The modified Rayon-based ACFs showed much higher adsorption capacity and longer breakthrough time for formaldehyde than did
as-prepared Rayon-based ACF. We proposed that the improvement of formaldehyde removal by modified ACFs was attributed to the
combined effects of physisorption contributed by pore structures and chemisorption contributed by the N-containing functional
groups, whereas there was only physisorption between the as-prepared ACF and formaldehyde molecules. 相似文献
17.
R. Leyva-Ramos M. S. Berber-Mendoza J. Salazar-Rabago R. M. Guerrero-Coronado J. Mendoza-Barron 《Adsorption》2011,17(3):515-526
In this work, the adsorption of Pb(II) from aqueous solution was investigated on various types of activated carbon fibers
(ACFs) manufactured from polyacrylonitrile and phenolic resin. The textural and physicochemical properties of the ACFs were
determined by the N2-BET method and acid-base titration. The experimental adsorption equilibrium data of Pb(II) on the ACFs were obtained in a
batch adsorber, and the Langmuir isotherm model better fitted the experimental data. The effects of the type of ACF and precursor
of ACF, solution pH and temperature upon the adsorption of Pb(II) on the ACFs were examined in detail. The adsorption capacity
was highly dependent upon the precursor of ACF. The Pb(II) adsorption capacity of the ACFs augmented when the solution pH
and temperature were increased from 2 to 4 and from 288 to 308 K, respectively. The effect of the pH was attributed to the
interactions between the surface of the ACF and Pb2+ ions present in the water solution. The Pb(II) adsorption capacity of the ACFs was enhanced by oxidation with HNO3 solution and the enhancement factor was between 1.1 and 1.4. The reversibility of the adsorption of Pb(II) was investigated
by first adsorbing Pb(II) on an ACF and then desorbing the Pb(II). It was noticed that Pb(II) was substantially desorbed from
ACF while reducing the solution pH to 2. It was concluded that the Pb(II) was mainly adsorbed on the ACFs by chemisorption,
electrostatic interactions and ion exchange. 相似文献
18.
Study of Static Adsorption Capacity of ACF for Xenon at 201 K 总被引:2,自引:0,他引:2
WANG Ya long ** ZHANG Hai tao WANG Xu hui ZHANG Li xing CHEN Li yun XIE Jin chuan 《高等学校化学研究》2002,18(2):216-220
IntroductionTheradioxenonsarenuclearfissionproducts .AccordingtotheComprehensiveNuclear Test BanTreaty (CTBT) ,thenucleareventswhichviolatethetreatymaybefoundbymonitoringradioxenonsinglobalatmospherewithInternationalMonitoringSys tem(IMS) .However ,allxenons… 相似文献
19.
利用聚丙烯腈基活性碳纤维(PAN-ACF)表面存在的羧基与氯化亚砜SOCl2发生酰氯化反应后与乙二胺110℃加热回流在其表面接枝胺基、酰胺基团对其进行改性,用傅立叶转换红外光谱仪(FTIR)、X射线光电子能谱仪(XPS)对改性前后活性碳纤维的表面结构和元素结合态及含量变化进行了表征,并将改性后的活性碳纤维(NH-ACF)应用于水体中Cu2+离子的去除处理,用电感耦合等离子体原子发射光谱仪(ICP-AES)检测被处理溶液中的Cu2+离子浓度变化,进而得出Cu2+离子在NH-ACF上的最大吸附量qmax.结果表明,NH-ACF比未改性处理的PAN-ACF对Cu2+吸附去除能力具有显著的优势,前者约为后者的1.5倍. 相似文献