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N-doped mesoporous alumina for adsorption of carbon dioxide

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Journal of Environmental Sciences 2012年第11期24卷 1979-1984页

作者： Jayshri A.Thote Ravikrishna V.Chatti Kartik S.Iyer Vivek Kumar Arti N.Valechha Nitin K.Labhsetwar Rajesh B.Biniwale M.K.N.Yenkie Sadhana S.Rayalu Environmental Materials Division National Environmental Engineering Research Institute (NEERI-CSIR)Nagpur 440020India. Lakshminarayan Institute of Technology Nagpur 440001India

N-doped mesoporous alumina has been synthesized using chitosan as the biopolymer template. The adsorbent has been thoroughly investigated for the adsorption of CO2 from a simulated flue gas stream （15% CO2 balanced with N2） and compared with commercially available mesoporous alumina procured from SASOL, Germany. CO2 adsorption was studied under different conditions of pre- treatment and adsorption temperature, inlet CO2 concentration and in the presence of oxygen and moisture. The adsorption capacity was determined to be 29.4 nag CO2/g of adsorbent at 55℃. This value was observed to be 4 times higher in comparison to that of commercial mesoporous alumina at a temperature of 55℃. Basicity of alumina surface coupled with the presence of nitrogen in template in synthesized sample is responsible for this enhanced CO2 adsorption. Adsorption capacity for CO2 was retained in the presence of oxygen; however moisture had a deteriorating effect on the adsorption capacity reducing it to nearly half the value.

关键词： mesoporous alumina chitosan carbon dioxide adsorption flue gas

Preparation of mesoporous alumina with large pore size and their supported rhenium oxide catalysts in metathesis of 1-butene and 2-butene to propene

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Journal of Natural Gas Chemistry 2012年第3期21卷 352-359页

作者： Lei Sang Sheng-Li Chen Guimei Yuan Zheng Zhou Rui Li Aicheng Chen Min Zheng Ju You State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of PetroleumBeijing 102249China

mesoporous γ-aluminas with large pore size （up to 19 nm, denoted as MAI9） are prepared from dispersed pseudo-boehmite using pluronic P123 as template. It is found that these mesoporous alumina supported rhenium oxide catalysts were more active and have far longer working life-span in gas-phase metathesis of 1-butene and 2-butene to propene than rhenium oxide on conventional alumina with small pore size （5 nm）. At 60 ℃ and atmospheric pressure with WHSV = 1 h^-1, the similar stable conversions of butene （ca. 55%） for all the 13 wt% Re207/alumina catalysts were obtained near the chemical equilibrium, and the stable working life-spans of Re2OT/MA19 were far longer than that of Re2O7/A1203, being about 70 h and 20 h, respectively.

关键词： mesoporous alumina rhenium oxide metathesis butene propene

Thermally stable lanthanum-doped mesoporous alumina as a stable support for palladium in catalytic oxidation of C_3H_8

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Journal of Rare Earths 2013年第11期31卷 1081-1084页

作者：江莉龙王玉玲王秀云罗永晋曹彦宁魏可镁 National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou University

High thermally stable mesoporous alumina doped with lanthanum was synthesized using inorganic nitrates as precursors and employing pluronic P123 （P123, （EO20PO70EO20, EO=ethylene oxide, PO=propylene oxide）） as a structure-directing agent. After calcination at 400 oC, the resultant lanthanum doped alumina exhibited aγ-Al2O3 phase, which was the same as pure alumina. After the thermal treatment up to 1200 oC, La-doped Al2O3 generated only one phase ofθ-Al2O3 rather than two mixed phase ofθ-Al2O3 andα-Al2O3 and the surface area could still maintain 101 m2/g with a keeping pore volume of 0.66 cm3/g. The excellent thermal sta-bility was explained by the titration of strong Lewis acid sites ofγ-Al2O3 with the assistance of highly dispersed lanthanum species covering on alumina. Furthermore, the lanthanum modified mesoporous alumina was preliminarily employed as a stable support for Pd in the catalytic oxidation of C3H8.

关键词： lanthanum thermal stability mesoporous alumina calcination rare earths

Synthesis and Characterization of mesoporous alumina via a Reverse Precipitation Method

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Journal of Materials Science & Technology 2012年第6期28卷 572-576页

作者： Y.S.Wu J.Ma F.Hu M.C.Li College of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

mesoporous aluminaΥ-AI203 with high specific surface area and large pore volume is prepared by using a facile reverse precipitation method from sodium aluminate and nitric acid. The effects of terminal pH value, aging time and thermal stability on the characterization of Υ-Al2Oa are studied by means of X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, Brunauer-Emmett-Teller （BET） method and scanning electron microscopy （SEM）. The results show that Υ-A1203 with better properties can be obtained by changing the preparation parameters. High BET surface area of 340 m2/g can be obtained by calcining at 500℃ for 4 h with large pore volume of 0.90 cm3/g and average pore size of 7.6 nm. After calcining at 1000°, the surface area is still 86 m2//g and the pore volume is 0.37 cm31/g.

关键词： mesoporous alumina Reverse precipitation Thermal stability

An Experimental Study of the Performance of Isomorphically Zirconium-Substituted mesoporous alumina Supported Cobalt Catalysts in Fischer-Tropsch Synthesis

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Advances in Chemical Engineering and Science 2022年第1期12卷 40-53页

作者： Sabar Simanungkalit Mingming Zhu Gia Hung Pham Zhezi Zhang Dongke Zhang Centre for Energy (M473) The University of Western Australia Crawley Australia

A series of mesoporous alumina (MA) supported cobalt (Co/MA) catalysts with MA isomorphically substituted by zirconium (Zr) were synthesised and evaluated for their performance in the Fischer-Tropsch synthesis. The Zr/(Zr + Al) atomic ratios varied from 1% - 15%. A zirconium-impregnated Co/MA catalyst prepared by wet impregnation with a Zr/(Zr + Al) atomic ratio of 5% was also evaluated to examine Zr incorporation’s effect method. The catalysts synthesised were characterised using N2 adsorption-desorption, X-ray Powder Diffraction (XRD), Transmission Electron Microscopy (TEM), and X-Ray Photoelectron Spectroscopy (XPS). It was found that Zr4+ ions were incorporated into the framework of MA and kept intact up to a Zr/(Zr + Al) atomic ratio of 5%. The cobalt dispersion and reducibility were improved as the Zr/(Zr + Al) atomic ratio increased to 50%. The performance of these catalysts for Fischer-Tropsch synthesis was evaluated using a fixed bed reactor at temperature and pressure of 493 K and 20 bar, respectively. The feed syngas had an H2/CO ratio of 2, diluted with 10% Ar. For isomorphically Zr-substituted Co/MA, the CO conversion and selectivity of diesel (C10 - C20) increased

关键词： Cobalt Catalyst Fischer-Tropsch Synthesis Isomorphic Substitution mesoporous alumina Zirconium

Ordered mesoporous alumina for Adsorptive Removal of Low Concentration of Fluoride from Drinking Water

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Ordered Mesoporous Alumina for Adsorptive Removal of Low Con...

Facile Synthesis of mesoporous γ-alumina using Starch as Template

中国颗粒学会超微颗粒专委会2013年年会暨第八届海峡两岸超微颗粒学术研讨会

作者： Ruofang Zhang Xike Tian Baodan Zhang Chao Yang Suxin Zhang Yanxin Wang Faculty of Material Science and Chemistry China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences School of Environmental Studies China University of Geosciences

Two kinds of crystalline and mesoporous alumina samples were prepared using aluminium isopropoxide as precursor and P123 as template *** are labeled OMA- 800 and OMA-400 in this paper,and tested for adsorptive removal of fluoride in water. Compared with OMA-800,OMA-400 which is cost-effective combined with excellent thermal stability has narrower pore size distribution,larger surface and larger pore volume.

关键词： Adsorption mesoporous alumina Low concentration fluorine ion Aluminium isopropoxide

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China Petroleum Processing & Petrochemical Technology 2009年第2期11卷 53-55页

作者： Xu Benjing Long Jun Tian Huiping Zhu Yuxia(SINOPEC Research Institute of Petroleum Processing,Beijing 100083) SINOPEC Research Institute of Petroleum Processing Beijing 100083 China

mesoporous alumina was prepared by using starch as the structure-directing template in an aqueous system. The resultant samples were characterized by using different methods such as the X-ray diffractometry,the transmission electron microscopy,the nitrogen adsorption-desorption analysis and the solid MAS NMR. The results showed that the prepared mesoporous γ-alumina had high surface area and uniform pore size distribution,and its specific surface area and the pore size could be tuned by changing the pH value of the starting solution.

关键词： mesoporous alumina starch template

Synthesis and Performance of mesoporous Phosphotungstic Acid/alumina Composite as a Novel Oxidative Desulfurization Catalyst

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Journal of Wuhan University of Technology(Materials Science) 2014年第2期29卷 237-241页

作者：颜学敏 XIONG Lin MEI Ping College of Chemistry and Environmental Engineering Yangtze University

A series of mesoporous phosphotungstic acid/alumina composites （HPW/Al_2O_3） with various HPW contents were synthesized by evaporation-induced self-assembly method. These composites were characterized by nitrogen adsorption-desorption, TEM, FTIR, and UV-vis, and were tested as catalysts in oxidation desulfurization of model fuel composed of dibenzothiophene （DBT） and hydrocarbon, using H202 as the oxidant. These composites exhibited high activity in catalytic oxidation of DBT in model fuel and good reusing ability. The best performance was achieved by using the mesoporous HPW/Al_2O_3 with 15wt% HPW content, which resulted in a DBT conversion of 98% after 2 h reaction at 343 K, and it did not show significant activity degradation after 3 recycles. Characterization results showed that the mesoporous structure of alumina and the Keggin structure of HPW were preserved in the formed composite. These results suggested that HPW/ Al_2O_3 could be a promising catalyst in oxidative desulfurization process.

关键词： mesoporous alumina tungstophosphoric acid oxidative desulfurization catalyst

Rh_2O_3/mesoporous MO_x-Al_2O_3(M = Mn,Fe,Co,Ni,Cu,Ba)catalysts:Synthesis,characterization,and catalytic applications

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Chinese Journal of Catalysis 2016年第1期37卷 73-82页

作者：刘欢林毅马臻复旦大学环境科学与工程系上海市大气颗粒物污染与防治重点实验室上海200433

Recently,a one-pot self-assembly method was proposed for the synthesis of mesoporous Al2O3 and MOx-Al2O3 composite ***,few attempts have been made to use mesoporous MOx-Al2O3 composites to support metal oxides for *** the present work,mesoporous MOx-Al2O3（M = Mn,Fe,Co,Ni,Cu,Ba）materials were prepared by a one-pot self-assembly method using Pluronic P123 as a structure-directing *** obtained mesoporous materials were loaded with Rh2O3 nanoparticles via impregnation with Rh（NO3）3 followed by calcination in air at 500°*** resulting catalysts were characterized by X-ray diffraction,N2 adsorption-desorption measurements,transmission electron microscopy,inductively coupled plasma optical emission spectrometry,X-ray photoelectron spectroscopy,and their catalytic activity and stability for CO oxidation and N2O decomposition were *** Rh2O3 nanoparticles were found to be on the order of1 nm in size and were highly dispersed on the high surface area mesoporous MOx-Al2O3 supports.A number of the Rh2O3/mesoporous MOx-Al2O3 catalysts exhibited higher catalytic activity than the Rh2O3/mesoporous Al2O3 prepared for comparison.

关键词： One-pot synthesis mesoporous alumina Metal oxide CO oxidation N2O decomposition