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X-氧化铝比表面积的测定 总被引:3,自引:0,他引:3
<正> 采用干燥器醇法测定γ-氧化铝(平均孔径30~60×10~(-10)米)的比表面积,测定数据准确、可靠。但是,使用干燥器醇法测定X-氧化铝(干燥剂用,平均孔径15~25×10~(-10)米)的比表面积时,测定的数据比静态BET法偏高,其原因是:①X-氧化铝的细孔半径较小,容易使乙醇分子产生毛细凝聚;② 相似文献
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采用双溶剂体系(硝酸铝和硝酸钴的乙醇溶液与钼酸铵的碳酸铵水溶液)共沉淀制备了氧化铝负载Co-Mo双金属氧化物。研究了双溶剂体系中乙醇和水的体积比对共沉淀的影响,考察了老化时间对氧化物结构参数的影响,研究了焙烧温度对氧化物还原性能的影响。结果表明:乙醇和水体积比对钼酸根离子的沉淀有重要影响,为了保证钼酸根离子的完全沉淀,乙醇的体积要随着MoO3负载量的增加而提高;随着老化时间的增加,氧化物的比表面积先增加后下降,6 h老化的样品具有最大的比表面积;低温焙烧制得的氧化物较容易还原。 相似文献
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金属有机骨架材料是一类新兴纳米多孔功能材料,研究出一种绿色环保的制备和活化金属有机骨架材料方法对于其工业应用具有重要的意义。应用机械化学法合成金属有机骨架材料(HKUST-1),并提出采用乙醇对所合成的材料进行活化和纯化,讨论不同溶剂(氯仿、乙醇)活化对合成的HKUST-1的孔隙结构和吸附性能的影响。研究结果表明:相对于传统水热法合成时间(24 h),无溶剂机械化学法反应时间缩短为30 min;活化溶剂对HKUST-1的比表面积和孔结构有较大的影响,乙醇比氯仿更容易置换出HKUST-1孔道中残留的前驱物,增大材料的比表面积,乙醇活化得到的HKUST-1比表面积高达1442.7 m2·g-1。在298 K、8 kPa条件下,乙醇活化得到的HKUST-1对苯的吸附容量高达6.90 mmol·g-1,比氯仿活化和水热法合成的HKUST-1对苯的吸附量高约25%,而且高于同等温度压力条件下活性炭、碳分子筛、沸石等常规吸附剂对苯的平衡吸附量。 相似文献
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打浆度与比表面积不能准确地反映出微纤维玻璃棉的直径分布情况,通过对生产上常用的6种不同打浆度数的微纤维玻璃棉分别进行比表面积测定、光学显微镜法直径测量及直径分布分析,证明了光学显微镜法更具有实际指导意义。 相似文献
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研究炭黑比表面积的测定方法。测定方法为:低温氮吸附法及统计厚度法。该方法样品用量小、速度快,结果准确。 相似文献
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Carbon cryogel as support of platinum nano-sized electrocatalyst for the hydrogen oxidation reaction
The kinetics of hydrogen oxidation reaction was studied in perchloric acid solution on carbon-supported Pt nanoparticles using the rotating disk electrode technique. Carbon cryogel and commercial carbon black. Vulcan XC-72 were used as catalyst supports. Pt/C catalysts were prepared by a modified polyol synthesis method in an ethylene glycol (EG) solution. Considerable effect has been observed for the specific surface area of carbon support on the fundamental properties of Pt/C catalyst, such as catalyst particle size distribution and dispersion as well as catalytic activity for the oxidation of hydrogen. X-ray diffraction (XRD) and transmission electron microscopy (TEM) images show that the particle size of the catalyst decreases with the increase of specific surface area of carbon support. Cyclic voltammetry (CV) was used for determination of the actual exposed surface area of catalyst particles. It was found that Pt catalyst prepared by using the novel carbon material displayed better hydrogen electrochemical oxidation activity than the catalyst prepared by using Vulcan XC-72. 相似文献
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光催化降解染料废水的研究 总被引:2,自引:0,他引:2
蒋朝俊 《化学工业与工程技术》2004,25(1):21-24
在光催化剂的固定化技术的研究中,通过化学反应将比表面积很小的TiO_2引入多孔硅胶载体颗粒的表面,并经过高温处理以提高其催化活性。通过BET比表面积测定发现,制得的光催化剂TSO具有比表面积大、分散性高和二次污染小等优点。而光催化降解实际染料废水的研究表明,制得的光催化剂对实际染料废水有较好的降解效果,强氧化剂H_2O_2的加入对染料废水的降解有利。利用钛醇盐水解法可以制备大量负载型TiO_2光催化剂,对于实际废水处理有一定的借鉴作用。 相似文献
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The present work describes a novel approach for the textural characterisation of a carbonaceous porous medium. Due to the electronic conduction properties of expanded natural graphite (ENG), electrochemical determination was proposed and the use of cyclic voltammetry enables determination of the surface area and porous volume of ENG. First, experiments were performed without the electrochemical electron transfer reaction. Then, the volume of the entire transformation of potassium hexacyanoferrate into the pores of the material was deduced by applying the rules of thin-layer electrochemistry. For the specific surface area and the porosity, the results are satisfying, but in comparison with classical methods, the electrochemical procedure does not allow the determination of the pore size distribution of the material. It is possible to evaluate the mean pore diameter and to assume that the double-layer capacitance may depend on the kind of graphite surface (basal or edge plane). 相似文献