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Dielectric barrier discharge plasma synthesis of Ag/γ-Al_(2)O_(3) catalysts for catalytic oxidation of CO
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作者 陶云明 胥月兵 +4 位作者 常宽 陈美玲 Sergey A STAROSTIN 许虎君 林良良 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第8期113-121,共9页
In this study,Ag/γ-Al_(2)O_(3)catalysts were synthesized by an Ar dielectric barrier discharge plasma using silver nitrate as the Ag source andγ-alumina(γ-Al_(2)O_(3))as the support.It is revealed that plasma can r... In this study,Ag/γ-Al_(2)O_(3)catalysts were synthesized by an Ar dielectric barrier discharge plasma using silver nitrate as the Ag source andγ-alumina(γ-Al_(2)O_(3))as the support.It is revealed that plasma can reduce silver ions to generate crystalline silver nanoparticles(Ag NPs)of good dispersion and uniformity on the alumina surface,leading to the formation of Ag/γ-Al_(2)O_(3)catalysts in a green manner without traditional chemical reductants.Ag/γ-Al_(2)O_(3)exhibited good catalytic activity and stability in CO oxidation reactions,and the activity increased with increase in the Ag content.For catalysts with more than 2 wt%Ag,100%CO conversion can be achieved at 300°C.The catalytic activity of the Ag/γ-Al_(2)O_(3)catalysts is also closely related to the size of theγ-alumina,where Ag/nano-γ-Al_(2)O_(3)catalysts demonstrate better performance than Ag/micro-γ-Al_(2)O_(3)catalysts with the same Ag content.In addition,the catalytic properties of plasma-generated Ag/nano-γ-Al_(2)O_(3)(Ag/γ-Al_(2)O_(3)-P)catalysts were compared with those of Ag/nano-γ-Al_(2)O_(3)catalysts prepared by the traditional calcination approach(Ag/γ-Al_(2)O_(3)-C),with the plasma-generated samples demonstrating better overall performance.This simple,rapid and green plasma process is considered to be applicable for the synthesis of diverse noble metal-based catalysts. 展开更多
关键词 DBD plasma plasma nanofabrication noble metal nanoparticles Co oxidation Ag/-al2o3 catalysts
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Al_(2)O_(3)在储能材料中的应用研究进展
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作者 王妍 魏诗诗 +2 位作者 赵昊雯 李健 王甲泰 《电源技术》 CAS 北大核心 2024年第8期1533-1540,共8页
Al_(2)O_(3)作为陶瓷材料、催化剂、催化剂载体及研磨磨料等有广泛的应用。因氧化铝具有优良的抗酸碱腐蚀性和力学等性能且热稳定性好、来源丰富,所以近年来逐渐开始应用在储能材料领域,进一步拓展了氧化铝的应用范围。主要针对氧化铝... Al_(2)O_(3)作为陶瓷材料、催化剂、催化剂载体及研磨磨料等有广泛的应用。因氧化铝具有优良的抗酸碱腐蚀性和力学等性能且热稳定性好、来源丰富,所以近年来逐渐开始应用在储能材料领域,进一步拓展了氧化铝的应用范围。主要针对氧化铝包覆后的二次储能电池正极材料、负极材料,以及改进隔膜的力学性能等方面进行研究。报道了近年来氧化铝在锂离子电池、钠离子电池、锂硫电池、电解液、隔膜方面的应用研究进展。 展开更多
关键词 储能材料 电极材料 al2o3 改性 电化学性能
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Modification of Nano-α-Al2O3 and Its Influence on the Surface Properties of Waterborne Polyurethane Resin Composite Passivation Films
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作者 Jiankang Fu Changshuai Ma +2 位作者 Yameng Zhu Jing Yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第5期29-48,共20页
Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub&... Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> was determined by nano-particle size analyzer, and the effects of nano-α-Al<sub>2</sub>O<sub>3</sub> content, ethanol-aqueous solution ratio and KH560 dosage on the dispersion and particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> were investigated. The material structure before and after modification was determined by Fourier transform infrared spectroscopy (FTIR). Aqueous polyurethane resin and inorganic components are combined with modified nano-α-Al<sub>2</sub>O<sub>3</sub> dispersion to form chromium-free passivation solution. The solution is coated on the galvanized sheet, the adhesion and surface hardness are tested, the bonding strength of the coating and the surface hardness of the substrate are discussed. The corrosion resistance and surface morphology of the matrix were investigated by electrochemical test, neutral salt spray test and scanning electron microscope test. The chromium-free passivation film formed after the modification of nano-α-Al<sub>2</sub>O<sub>3</sub> increases the surface hardness of galvanized sheet by about 85%. The corrosion resistance of the film is better than that of a single polyurethane film. The results show that the surface hardness and corrosion resistance of polyurethane resin composite passivation film are significantly improved by the introduction of nano-α-Al<sub>2</sub>O<sub>3</sub>. 展开更多
关键词 Micro-Nano α-al2o3 Waterborne Polyurethane Resin Particle Size Surface Hardness Corrosion Resistance
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NH_(3)SO_(3)改性稀土尾矿催化剂NH_(3)-SCR脱硝活性及SO_(2)/H_(2)O耐受性能研究
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作者 焦坤灵 焦晓云 +3 位作者 刘佳杰 汪思瀛 李娜 武文斐 《稀有金属与硬质合金》 CAS CSCD 北大核心 2024年第2期32-37,75,共7页
采用球磨、微波焙烧方法制备了不同质量分数NH_(3)SO_(3)改性稀土尾矿NH_(3)-SCR脱硝催化剂。通过BET、SEM-EDS、XRD、NH_(3)-TPD、H_(2)-TPR分析了催化剂脱硝活性及SO_(2)/H_(2)O耐受性能。结果表明:NH_(3)SO_(3)改性使催化剂脱硝活性... 采用球磨、微波焙烧方法制备了不同质量分数NH_(3)SO_(3)改性稀土尾矿NH_(3)-SCR脱硝催化剂。通过BET、SEM-EDS、XRD、NH_(3)-TPD、H_(2)-TPR分析了催化剂脱硝活性及SO_(2)/H_(2)O耐受性能。结果表明:NH_(3)SO_(3)改性使催化剂脱硝活性得到了显著提高,10%NH_(3)SO_(3)改性催化剂在300~350℃脱硝活性可达90%左右。SO_(2)/H_(2)O共同作用可将10%NH_(3)SO_(3)改性催化剂脱硝活性提高至97%,其促进作用保持了良好的稳定性,且具有可逆性。NH_(3)SO_(3)改性稀土尾矿后,催化剂比表面积、酸性位点及强度增加,表面活性物质分散度更高,弱化了尾矿矿物晶型,提高了催化剂吸附能力和氧化还原能力,从而提高催化脱硝活性,同时具备优良的SO_(2)/H_(2)O耐受性。 展开更多
关键词 NH_(3)So_(3)改性 稀土尾矿 催化剂 NH_(3)-SCR脱硝 So_(2)/H_(2)o耐受性能 脱硝活性
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Effect of Calcination Temperature on La-Modified Al2O3 Catalysts for Vapor Phase Hydrofluorination of Acetylene to Vinyl Fluoride 被引量:4
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作者 毕庆员 鲁继青 +2 位作者 邢丽琼 郭明 罗孟飞 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期89-94,I0002,共7页
A La-modified Al2O3 catalyst was prepared with deposition-precipitation method. The effect of calcination temperature on the reactivity for vapor phase hydrofluorination of acetylene to vinyl fluoride. The catalysts c... A La-modified Al2O3 catalyst was prepared with deposition-precipitation method. The effect of calcination temperature on the reactivity for vapor phase hydrofluorination of acetylene to vinyl fluoride. The catalysts calcined at different temperatures were characterized using NH3-TPD, pyridine-FTIR, X-ray diffraction, and Raman techniques. It was found that the calcination process could not only change the structure of these catalysts but also modify the amount of surface acidity on the catalysts. The catalyst calcined at 400 ℃ exhibited the highest conversion of acetylene (94.6%) and highest selectivity to vinyl fluoride (83.4%) and lower coke deposition selectivity (0.72%). The highest activity was related to the largest amount of surface acidity on the catalyst, and the coke deposition was also related to the total amount of surface acidic sites. 展开更多
关键词 La2o3-al2o3 catalyst Hydrofluorination reaction Vinyl fluoride ACETYLENE Calcination temperature
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CO Low-Temperature Oxidation over Au/MO_x/Al_2O_3 Catalysts 被引量:1
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作者 WANGDonghui HAOZhengping 《催化学报》 SCIE CAS CSCD 北大核心 2002年第6期489-490,共2页
关键词 一氧化碳 低温氧化 au/Mox/al2o3 氧化铝 负载型催化剂
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Study on Au/Al_2O_3 catalysts for low-temperature CO oxidation in situ FT-IR
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作者 Xuhua Zou Shixue Qi +3 位作者 Jinguang Xu Zhanghuai Suo Lidun An Feng Li 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第3期307-312,共6页
Au/Al2O3 catalyst was prepared by a modified anion impregnation method and investigated with respect to its initial activity and stability for low-temperature CO oxidation.The activity changes of the catalyst were exa... Au/Al2O3 catalyst was prepared by a modified anion impregnation method and investigated with respect to its initial activity and stability for low-temperature CO oxidation.The activity changes of the catalyst were examined after separate treatment in CO+O2 or CO2 +O2 .Furthermore,in situ FT-IR studies were performed to investigate the species on the surface when CO or CO+O2 or CO2 +O2 was selected separately as adsorption gas.The results showed that Au/Al2O3 catalyst exhibited very high initial activity,but the catalytic activity was found to decrease gradually during CO oxidation with time on stream.And also,the activity of the catalyst declined after treatment in CO+O2 or CO2 +O2 .The formation and accumulation of carbonate-like species during CO oxidation or treatment in CO+O2 or CO2 +O2 might be mainly responsible for the activity decrease,which was reversible. 展开更多
关键词 supported gold catalyst au/al2o3 Co oxidation catalytic activity STABILITY in situ FT-IR
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Al/Cr_(2)O_(3)对硝化棉热分解过程的影响
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作者 赵宁宁 马海霞 +2 位作者 姚二岗 安亭 赵凤起 《火炸药学报》 EI CAS CSCD 北大核心 2023年第8期715-723,I0003,共10页
为了探讨Al/Cr_(2)O_(3)纳米铝热剂对硝化棉(NC)热分解过程的影响,采用差示扫描量热法(DSC)及热重/红外联用技术(TG/DTG-FTIR)研究了单组分NC和Al/Cr_(2)O_(3)/NC复合物的热分解反应过程。运用Kissinger法、Starink法、Kissinger-迭代法... 为了探讨Al/Cr_(2)O_(3)纳米铝热剂对硝化棉(NC)热分解过程的影响,采用差示扫描量热法(DSC)及热重/红外联用技术(TG/DTG-FTIR)研究了单组分NC和Al/Cr_(2)O_(3)/NC复合物的热分解反应过程。运用Kissinger法、Starink法、Kissinger-迭代法和Ozawa-迭代法计算得到NC及Al/Cr_(2)O_(3)/NC的表观活化能。通过FWO法、KAS法和Friedman法得到NC和Al/Cr_(2)O_(3)/NC热分解过程的动力学参数,并引入修正后的?esták-Berggren经验方程对相应热分解反应动力学模型进行重建。结果表明,Al/Cr_(2)O_(3)纳米铝热剂可使NC热分解反应的表观活化能降低33.7kJ/mol,热点火温度降低3.5℃,热爆炸临界温度降低3.0℃。Al/Cr_(2)O_(3)/NC的热分解反应过程遵循n级动力学方程f(α)=7.25α^(0.73)(1-α)^(2.12)。在Al/Cr_(2)O_(3)催化作用下,NC首先断裂O—NO_(2)键,最终释放H_(2)O、CO_(2)、CO、NO_(2)、NO、N_(2)O、HCHO和HCOOH气体产物。 展开更多
关键词 物理化学 al/Cr_(2)o_(3) 纳米铝热剂 硝化棉 NC 热分解动力学 燃烧催化剂 TG/DTG-FTIR
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Enhanced CO oxidation over potassium-promoted Pt/Al_2O_3 catalysts:Kinetic and infrared spectroscopic study 被引量:1
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作者 刘欢欢 贾爱平 +2 位作者 王瑜 罗孟飞 鲁继青 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1976-1986,共11页
A series of K-promoted Pt/Al2O3 catalysts were tested for CO oxidation. It was found that the addition of K significantly enhanced the activity. A detailed kinetic study showed that the activation energies of the K-co... A series of K-promoted Pt/Al2O3 catalysts were tested for CO oxidation. It was found that the addition of K significantly enhanced the activity. A detailed kinetic study showed that the activation energies of the K-containing catalysts were lower than those of the K-free ones, particularly for catalysts with high Pt contents (51.6 k)/mol for 0.42K-2.0Pt/Al2O3 and 6:3.6 kJ/mol for 2.0Pt/Al2O3 ). The CO reaction orders were higher for the K-containing catalysts (about -0.2) than for the K-free ones (about -0.5), with the former having much lower equilibrium constants for CO adsorption than the latter. In situ Fourier-transform infrared spectroscopy showed that surface CO desorption from the 0.42K-2.0Pt/Al2O3 catalyst was easier than from 2.0Pt/Al2O3. The promoting effect of K was therefore caused by weakening of the interactions between CO and surface Pt atoms. This decreased coverage of the catalyst with CO and facilitated competitive O2 chemisorption on the Pt surface, and significantly lowered the reaction barrier between chemisorbed CO and O2 species. 展开更多
关键词 Co oxidation Potassium Kinetics Pt/al2o3 catalyst Promoting effect
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Methanation of syngas over coral reef-like Ni/Al_2O_3 catalysts 被引量:23
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作者 Shengli Ma Yisheng Tan Yizhuo Han 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2011年第4期435-440,共6页
Coral reef-like Ni/Al2O3 catalysts were prepared by co-precipitation of nickel acetate and aluminium nitrate with sodium carbonate aqueous solution in the medium of ethylene glycolye.Methanation of syngas was carried ... Coral reef-like Ni/Al2O3 catalysts were prepared by co-precipitation of nickel acetate and aluminium nitrate with sodium carbonate aqueous solution in the medium of ethylene glycolye.Methanation of syngas was carried out over coral reef-like Ni/Al2O3 catalysts in a continuous flow type fixed-bed reactor.The structure and properties of the fresh and used catalysts were studied by SEM,N2 adsorption-desorption,XRD,H2-TPR,O2-TPO,TG and ICP-AES techniques.The results showed that the coral reef-like Ni/Al2O3 catalysts exhibited better activity than the conventional Ni/Al2O3-H2O catalysts.The activities of coral reef-like catalysts were in the order of Ni/Al2O3-673Ni/Al2O3-573Ni/Al2O3- 473Ni/Al2O3-773.Ni/Al2O3-673-EG catalyst showed not only good activity and improved stability but also superior resistance to carbon deposition,sintering,and Ni loss.Under the reaction conditions of CO/H2(molar ratio)=1:3,593 K,atmospheric pressure and a GHSV of 2500 h-1,CH4 selectivity was 84.7%,and the CO conversion reached 98.2%. 展开更多
关键词 METHANATIoN SYNGAS coral reef-like Ni/al2o3 catalysts CalCINATIoN
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Investigation of the characteristics and deactivation of catalytic active center of Cr-Al_2O_3 catalysts for isobutane dehydrogenation 被引量:9
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作者 Deren Fang Jinbo Zhao +4 位作者 Wanjun Li Xu Fang Xin Yang Wanzhong Ren Huimin Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第1期101-107,共7页
Deactivation mechanism of Cr-Al2O3catalyst and the interaction of Cr-A1 in the dehydrogenation of isobutane, as well as the nature of the catalytic active center, were studied using XRD, SEM, XPS, H2-TPR, isobutane-TP... Deactivation mechanism of Cr-Al2O3catalyst and the interaction of Cr-A1 in the dehydrogenation of isobutane, as well as the nature of the catalytic active center, were studied using XRD, SEM, XPS, H2-TPR, isobutane-TPR and TPO techniques. The results revealed that the deactivation of Cr-Al2O3 catalyst was mainly caused by carbon deposition on its surface. The Cr3+ ion could not be reduced by hydrogen but could be reduced to Cr2+ by hydrocarbons and monoxide carbon. The active center for isobutane dehydrogenation could be Cr2+/Cr3+ produced from Cr6+ by the on line reduction of hydrocarbon and carbon monoxide. The binding energy of Al3+ was strongly affected by the state of chromium cations in the catalysts. 展开更多
关键词 isobutane dehydrogenation Cr/al2o3 DEACTIVATIoN active center catalyst
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Ethanol steam reforming over Ni-Cu/Al_2O_3-M_yO_z (M = Si, La, Mg,and Zn) catalysts 被引量:5
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作者 Lifeng Zhang Jie Liu Wei Li Cuili Guo Jinli Zhang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第1期55-65,共11页
Ni-based catalysts doped with copper additives were studied on their role in ethanol steam reforming reaction. The effects of Cu content, support species involving Al2O3-SIO2, Al2O3-MgO, Al2O3-ZnO, and Al2O3-La2O3, on... Ni-based catalysts doped with copper additives were studied on their role in ethanol steam reforming reaction. The effects of Cu content, support species involving Al2O3-SIO2, Al2O3-MgO, Al2O3-ZnO, and Al2O3-La2O3, on the catalytic performance were studied. Characterizations by TPR, XRD, NH3-TPD, XPS, and TGA indicated that catalysts 30Ni5Cu/Al2O3-MgO and 30Ni5Cu/Al2O3-ZnO have much higher H2 selectivity than 30Ni5Cu/Al2O3-SiO2, as well as good coke resistance. H2 selectivity for 30Ni5Cu/Al2O3-MgO catalyst was 73.3% at 450 ℃ and increased to 94.0% at 600℃, whereas for 30Ni5Cu/Al2O3-ZnO catalyst, the H2 selectivity was 63.6% at 450 ℃ and 95.2% at 600℃. TheseAl2O3-MgO and Al2O3-ZnO supported Ni-Cu bimetallic catalysts may have important applications in the production of hydrogen by ethanol steam reforming reactions. 展开更多
关键词 ethanol steam reforming nickel-copper-based catalyst al2o3-So2 support al2o3-Mgo support al2o3-Zno support al2o3-La2o3 support
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Effect of Al_2O_3 Binder on the Precipitated Iron-Based Catalysts for Fischer-Tropsch Synthesis 被引量:6
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作者 Hai-Jun Wan Bao-Shan Wu +4 位作者 Xia An Ting-Zhen Li Zhi-Chao Tao Hong-Wei Xiang Yong-Wang Li 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第2期130-138,共9页
A series of iron-based Fischer-Tropsch synthesis (FTS) catalysts incorporated with Al2O3 binder were prepared by the combination of co-precipitation and spray drying technology. The catalyst samples were characteriz... A series of iron-based Fischer-Tropsch synthesis (FTS) catalysts incorporated with Al2O3 binder were prepared by the combination of co-precipitation and spray drying technology. The catalyst samples were characterized by using N2 physical adsorption, temperature-programmed reduction/desorption (TPR/TPD) and MSssbauer effect spectroscopy (MES) methods. The characterization results indicated that the BET surface area increases with increasing Al2O3 content and passes through a maximum at the Al2O3/Fe ratio of 10/100 (weight basis). After the point, it decreases with further increase in Al2O3 content. The incorporation of Al2O3 binder was found to weaken the surface basicity and suppress the reduction and carburization of iron-based catalysts probably due to the strong K-Al2O3 and Fe-Al2O3 interactions. Furthermore, the H2 adsorption ability of the catalysts is enhanced with increasing Al2O3 content. The FTS performances of the catalysts were tested in a slurry-phase continuously stirred tank reactor (CSTR) under the reaction conditions of 260 ℃, 1.5 MPa, 1000 h^-1 and molar ratio of H2/CO 0.67 for 200 h. The results showed that the addition of small amounts of Al2O3 affects the activity of iron-based catalysts to a little extent. However, with further increase of Al2O3 content, the FTS activity and water gas shift reaction (WGS) activity are decreased severely. The addition of appropriate Al2O3 do not affect the product selectivity, but the catalysts incorporated with large amounts of Al2O3 have higher selectivity for light hydrocarbons and lower selectivity for heavy hydrocarbons. 展开更多
关键词 Fischer-Tropsch synthesis iron-based catalyst al2o3 binder Fe-al2o3 interaction
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Support Effects on Thiophene Hydrodesulfurization over Co-Mo-Ni/Al_2O_3 and Co-Mo-Ni/TiO_2-Al_2O_3 Catalysts 被引量:7
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作者 刘超 周志明 +2 位作者 黄永利 程振民 袁渭康 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第4期383-391,共9页
A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 &#176;C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonate... A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 &#176;C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonated cata-lyst (SC) had aromatic structure, composed of carbon enriched inner core, and oxygen-containing (SO3H, COOH, OH) groups enriched surface. The SO3H, COOH, OH groups amounted to 0.74 mmol·g^-1, 0.78 mmol·g^-1, 2.18 mmol·g^-1, respectively. The fresh SC showed much higher catalytic activity than that of the traditional solid acid catalysts (strong-acid 732 cation exchange resin, hydrogen type zeolite socony mobile-five (HZSM-5), sulfated zir-conia) in esterification of oleic acid. SC was deactivated during the reactions, through the mechanisms of leaching of sulfonated species and formation of sulfonate esters. Two regeneration methods were developed, and the catalytic activity can be mostly regenerated by regeneration Method 1 and be fully regenerated by regeneration Method 2, respectively. 展开更多
关键词 HYDRoDESULFURIZATIoN SUPPoRT hierarchically macro-/mesoporous structure al2o3 Tio2-al2o3
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Effect of Alumina Particle Size on Ni/Al2O3 Catalysts for p-Nitrophenol Hydrogenation 被引量:5
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作者 陈日志 杜艳 +1 位作者 邢卫红 徐南平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期884-888,共5页
The catalytic hydrogenation of p-nitrophenol to p-aminophenol was investigated over Ni/Al2O3 catalyst on alumina support with different particle size. It is found that support particle size has significant influences ... The catalytic hydrogenation of p-nitrophenol to p-aminophenol was investigated over Ni/Al2O3 catalyst on alumina support with different particle size. It is found that support particle size has significant influences on physiochemical properties and catalytic activity of the resulting Ni/Al2O3 catalyst, but little influence on the selec-tivity. At a comparable amount of Ni loading, the catalytic activity of Ni/Al2O3 prepared with alumina support of smaller particle size is lower. The reduction behavior of the catalyst is a key factor in determining the catalytic activity of Ni/Al2O3 catalyst. The supported nickel catalyst 10.3Ni/Al2O3-3 improves the life span of the membrane by reducing fouling on the membrane surface compared to nano-sized nickel. 展开更多
关键词 P-NITRoPHENoL catalytic hydrogenation P-AMINoPHENoL Ni/al2o3 catalysts ceramic membrane filtration
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Preparation of Fe_2P/Al_2O_3 and FeP/Al_2O_3 catalysts for the hydrotreating reactions 被引量:3
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作者 Yamei Yuan Jiayou Zhang +2 位作者 Hui Chen Qiumei Hou Jianyi Shen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第2期116-121,共6页
A 60%Fe/Al_2O_3 catalyst was prepared by the co-precipitation method.It was reduced by H_2 to produce metallic Fe,which was then sulfided by CS_2 to Fe_(0.96) S and Fe_3S_4 or phosphided by triphenylphosphine(PPh3) in... A 60%Fe/Al_2O_3 catalyst was prepared by the co-precipitation method.It was reduced by H_2 to produce metallic Fe,which was then sulfided by CS_2 to Fe_(0.96) S and Fe_3S_4 or phosphided by triphenylphosphine(PPh3) in liquid phases to Fe2 P and Fe P.It was found that the iron sulfides(Fe0.96 S and Fe_3S_4) exhibited the low activity for the hydrodesulfurization(HDS) reactions.The HDS activity was also low on the Fe(metal)/Al_2O_3 and Fe_2 P/Al_2O_3 catalysts since they were converted into Fe0.96 S and Fe_3S_4 during the HDS reactions.In contrast,the FeP/Al_2O_3 was found to be stable and active for the HDS reactions.In particular,Fe P/Al_2O_3 possessed significantly smaller Fe P particles than Fe P/C,leading to the significant higher HDS activity of FeP/Al_2O_3 than Fe P/C. 展开更多
关键词 Fe2P/al2o3 catalyst FeP/al2o3 catalyst Liquid phase phosphidation PPh3 HYDRoTREATING REACTIoNS
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DBD coupled with MnOx/γ-Al2O3 catalysts for the degradation of chlorobenzene 被引量:4
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作者 Yanghaichao LIU Liping LIAN +2 位作者 Weixuan ZHAO Renxi ZHANG Huiqi HOU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第3期115-122,共8页
This paper investigates the degradation of chlorobenzene by dielectric barrier discharge(DBD)coupled with MnOx/γ-Al2O3 catalysts.MnOx/γ-Al2O3 catalysts were prepared using the impregnation method and were characteri... This paper investigates the degradation of chlorobenzene by dielectric barrier discharge(DBD)coupled with MnOx/γ-Al2O3 catalysts.MnOx/γ-Al2O3 catalysts were prepared using the impregnation method and were characterized in detail by N2 adsorption/desorption,x-ray diffraction and x-ray photoelectron spectroscopy.Compared with the single DBD reactor,the coupled reactor has a better performance on the removal rate of chlorobenzene,the selectivity of COx,and the inhibition of ozone production,especially at low discharge voltages.The degradation rate of chlorobenzene and selectivity of COx can reach 96.3%and 53.0%,respectively,at the specific energy density of 1350 J l-1.Moreover,the ozone concentration produced by the discharge is significantly reduced because the MnOx/Al2O3 catalysts contribute to the decomposition of ozone to form oxygen atoms for the oxidation of chlorobenzene.In addition,based on analysis of the byproducts,the decomposition mechanism of chlorobenzene in the coupled reactor is also discussed. 展开更多
关键词 PLASMA catalytsis system chlorinated VoCS Mnox/al2o3 catalysts
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Sub-nanometer-thick Al2O3 Overcoat Remarkably Enhancing Thermal Stability of Supported Gold Catalysts
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作者 王春雷 路军岭 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第5期571-577,I0001,共8页
Supported gold nanoparticle catalysts show extraordinarily high activity in many reactions. While the relative poor thermal stability of Au nanoparticles against sintering at elevated temperatures severely limits thei... Supported gold nanoparticle catalysts show extraordinarily high activity in many reactions. While the relative poor thermal stability of Au nanoparticles against sintering at elevated temperatures severely limits their practical applications. Here atomic layer deposition (ALD) of TiO2 and Al2O3 was performed to deposit an Au/TiO2 catalyst with precise thickness con-trol, and the thermal stability was investigated. We surprisingly found that sub-nanometer-thick Al2O3 overcoat can su ciently inhibit the aggregation of Au particles up to 600 C in oxygen. On the other hand, the enhancement of Au nanoparticle stability by TiO2 overcoat is very limited. Di use reffectance infrared Fourier transform spectroscopy (DRIFTS) of CO chemisorption and X-ray photoelectron spectroscopy measurements both con rmed the ALD overcoat on Au particles surface and suggested that the presence of TiO2 and Al2O3 ALD overcoat on Au nanoparticles does not considerably change the electronic properties of Au nanoparticles. The catalytic activities of the Al2O3 overcoated Au/TiO2 catalysts in CO oxidation increased as increasing calcination temperature, which suggests that the embed-ded Au nanoparticles become more accessible for catalytic function after high temperature treatment, consistent with our DRIFTS CO chemisorption results. 展开更多
关键词 au/TIo2 SINTERING Atomic layer deposition al2o3 overcoat Nanoparticlestability
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Effects of Cerium Oxide on Ni/Al_2O_3 Catalysts for Decomposition of CH_4 and C_2H_4 被引量:4
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作者 杨咏来 李文钊 徐恒泳 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第4期427-429,共3页
Characteristics of carbon deposition of CH 4 and C 2H 4 decomposition over supported Ni and Ni Ce catalysts were studied by using a pulse reaction as well as BET, TPR, XPS and hydrogen chemisorption techniques. It... Characteristics of carbon deposition of CH 4 and C 2H 4 decomposition over supported Ni and Ni Ce catalysts were studied by using a pulse reaction as well as BET, TPR, XPS and hydrogen chemisorption techniques. It is found that there is a metal semiconductor interaction (MScI) in the Ni Ce catalyst, and the effect of MScI on the carbon deposition of CH 4 decomposition is opposite to that of C 2H 4. A novel model of carbon deposition of CH 4 or C 2H 4 decomposition was proposed. 展开更多
关键词 catalytic chemistry Ni/al 2o 3 catalyst cerium oxide METHANE ETHYLENE DECoMPoSITIoN rare earths
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Research on KOH/La-Ba-Al_2O_3 catalysts for biodiesel production via transesterification from microalgae oil 被引量:7
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作者 Xiaoyu Zhang Qing Ma +3 位作者 Bibo Cheng Jun Wang Jinshan Li Fude Nie 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第6期774-779,共6页
Alumina supports modified by lanthanum (La) and barium (Ba) were prepared by peptization. Catalysts with different KOH contents supported on modified alumina were prepared by impregnation method. Various technique... Alumina supports modified by lanthanum (La) and barium (Ba) were prepared by peptization. Catalysts with different KOH contents supported on modified alumina were prepared by impregnation method. Various techniques, including N2 adsorption-desorption (Brunauer-Emmet-Teller method, BET), X-ray diffraction (XRD), scanning electron microscopy (SEM), and fourier transform infrared absorption spectroscopy (FT-IR). Catalytic activity for microalgae oil conversion to methyl ester via transesterification was evaluated and analyzed by GC-MS and GC. BET results showed that the support possessed high specific surface area, suitable pore volume and pore size distribution. Activity results indicated that the catalyst with 25 wt% KOH showed the best activity for microalgae oil conversion. XRD and SEM results revealed that Al-O-K compound was the active phase for microalgae oil conversion. The agglomeration and changing of pore structure should be the main reasons for the catalyst deactivation when KOH content was higher than 30 wt%. 展开更多
关键词 biodiesel microalgae oil LA2o3 BAo solid catalyst
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