共查询到19条相似文献,搜索用时 171 毫秒
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活性炭的孔结构和表面特性对其油气吸附性能有着十分重要的影响。本文对市售活性炭分别采用活化和氢还原的方法进行处理,采用N_2吸附、IR、元素分析等表征方式研究活性炭处理前后的结构性能,探究活性炭的表面与孔结构特性对其油气吸附性能的影响。结果表明:经高温水蒸气活化和氢还原处理后,活性炭的孔结构和表面含氧基团均发生改变,对活性炭油气吸附性能有较大的影响。其中活性炭的孔结构特性对其吸附油气能力起决定作用,经水蒸气活化,孔径在1~2 nm之间的孔发达,对油气的穿透吸附量提高47.5%;经高温氢气处理后的活性炭,表面含氧量降低了23%,对油气的穿透吸附量提高23.9%。 相似文献
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活性炭纤维及其吸附特性 总被引:13,自引:0,他引:13
活性炭纤维(ACF)作为活性炭(AC)的第三代产品,被用作高性能吸附剂。通过对ACF制备过程,孔结构与表面化学结构的介绍,充分说明ACF其优异的吸附性能,以及吸附的有关理论知识。 相似文献
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以生物质柞木为原料,采用不同活化法制备具有不同结构特征的柞木基活性炭,利用N2吸附、FT-IR、XPS、XRD、Raman光谱等表征手段对活性炭的微结构特性进行解析,探究活化方式对活性炭微结构性能的影响;微结构与超级电容器性能的构效关系。研究表明: KOH和H3PO4-KOH法制备的活性炭微孔发达,炭结构表面缺陷位与杂原子丰富,在低电流密度下表现出更高的比电容;H3PO4-KOH法制备的活性炭具备更宽的微介孔分布与孔道连通性,使其具有更好的电容保持率;CO2、H3PO4和H3PO4-CO2法制备的活性炭介孔发达,微孔体积小,孔道连通性差,炭结构相对完整,裸露于炭结构表面的缺陷与杂原子相对较少,尽管电容保持率较高,但比电容较低。因此,高性能的超级电容器活性炭电极应具有发达的微孔结构、较宽的微介孔分布、通畅的微介孔连通结构,同时含有更多的裸露于炭结构表面的结构缺陷与杂原子基团,从而提高超级电容器的能量密度。 相似文献
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棉织物通过球磨预处理,制得棉纤维粉末并进行预溶解,高温碳化制备了活性炭。对预处理得到的棉粉末和制得的活性炭样品进行结构和形貌表征,并测试活性炭的吸附性能。结果表明,球磨预处理使棉纤维的形貌由纤维状态变为不规则块状,颜色变黑,有初步碳化的作用;棉纤维粉末结晶度降低,表面官能团减少;制得的活性炭含有孔结构,具有吸附性能,活性炭碘吸附值最高可达1 144 mg/g。 相似文献
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Hongxin Zhang Vinay V. Bhat Peter X. Feng Cristian I. Contescu Nidia C. Gallego 《Carbon》2012,50(14):5278-5285
Potassium-doped activated carbon was prepared by mixing potassium salt with polyfurfuryl alcohol precursor followed by carbonization and activation. Several experimental techniques, such as thermogravimetric analysis, gas adsorption, X-ray diffraction and Raman scattering spectroscopy were employed to understand the effects of potassium on the texture and pore structures of the activated carbon, which ultimately affects the hydrogen adsorption properties. After doping with potassium, the activated carbon exhibits higher surface area, higher micropore volume, and enhanced hydrogen adsorption capacity. Understanding of how alkali metals affect surface area and micropore development in activated carbon may help to clarify the hydrogen adsorption mechanism and improve the design of suitable carbon-based hydrogen storage materials. 相似文献
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活性炭纤维化学改性的研究现状与展望 总被引:1,自引:0,他引:1
介绍了活性炭纤维(ACF)的结构特点及表面化学组成,综述了近年来ACF化学改性的国内外研究进展,展望ACF化学改性的发展方向是将有机合成、纺丝、碳化学、表面化学、催化剂等化学原理充分利用于其开发过程,并结合化工单元过程技术,降低成本,推动ACF的应用。建议积极开发中孔ACF及特种聚丙烯腈类ACF产品。 相似文献
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含酚废水对环境和生物有较大危害,是一种常见的化工废水。活性炭作为良好的吸附剂被广泛用于污水处理,也常被用于吸附处理含酚废水。最新的研究集中于开发利用各种含碳原材料,并探究活性炭制备和改性方法,以改善活性炭对酚类的吸附性能。部分机理研究则关注活性炭的孔隙结构和表面官能团及其对吸附酚类性能的影响。本文从活性炭的制备和改性出发,归纳整理活性炭吸附酚类的特性和机理,分析吸附过程的主要影响因素,并对研究发展方向进行推论和展望。分析表明含碳量高的原材料适合制备活性炭,尤其是含碳废弃物。活性炭的苯酚吸附性能受比表面积和表面官能团的共同影响,这对于活性炭的制备和改性有指导意义。活性炭吸附苯酚的具体应用中,需要控制粒度、pH、温度、吸附时间和竞争吸附等影响因素。 相似文献
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This study was to investigate the catalytic effect of inorganic compositions present in fly ash carbons, high-unburned-carbon content fly ashes from coal-fired power plants, on the development of surface area during steam activation. Through this work, the relationships between the concentrations of alkali metals (Na and K) and a mixture of metals, Na-K-Ca and Na-K-Fe, in fly ash carbon and the surface areas of the produced activated carbon were studied.Six fly ash carbons were selected as feedstocks for activated carbon. SEM/EDS studies showed that there are two groups of inorganic particles present in fly ash carbons, in terms of the way they are associated with carbon particles: inorganic particles that exist as free single particles, and inorganic particles that are combined with the carbon particles. A series of froth flotation tests was conducted to separate the individual inorganic particles from the fly ash carbons. The concentration of the inorganic particles was analyzed using ICP-AES before and after froth flotation separation. Studies showed that the Na-K, Na-K-Ca, and Na-K-Fe which are combined with carbon particles had catalytic effects on the development of the surface areas of activated carbons. The higher the concentration of these catalytic particles, the more significant effects they had on the development of the surface areas with increasing carbon burn-off levels. 相似文献
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Ji Sun Im Jeen-Seok Jang Young-Seak Lee 《Journal of Industrial and Engineering Chemistry》2009,15(6):914-918
In our study, mesoporous carbon fibers were prepared by using electrospinning and physical activation. In order to develop mesoporous structure, silica was used as a physical activation agent due to meso-size of particle. The diameter of activated carbon fibers increased and surface became rougher after physical activation. Textural properties of carbon fibers were evaluated by using surface pore structure analysis apparatus. The specific surface area increased 12 times and total pore volume increased about 57 times through physical activation using silica. The development of mesoporous structure was confirmed by pore size distribution and fraction of micropore volume. From the DFT pore size distribution, it is sure that broad meso-sized porous carbon fibers were obtained from physical activation in our experiment. The fact that fractions of micropore volume are too low showing less than 2% by the results of total pore volume and HK pore volume concedes that silica activated CFs are pretty mesoporous. Eventually activated carbon fibers having broad meso-sized pores were obtained successfully. 相似文献