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Novel promoting effects of cerium on the activities of NO_x reduction by NH_3 over TiO_2-SiO_2-WO_3 monolith catalysts 认领 引用 被引量:15
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作者 房志涛 林涛 +3 位作者 徐海迪 吴干学 孙萌萌 陈耀强 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第10期952-959,共8页
A series of catalysts were prepared by doping different loadings of CeO2 over TiO2-SiO2-WO3 and used for the selective catalytic reduction of NOx by NH3. The experimental results showed that the selective catalytic re... A series of catalysts were prepared by doping different loadings of CeO2 over TiO2-SiO2-WO3 and used for the selective catalytic reduction of NOx by NH3. The experimental results showed that the selective catalytic reduction(SCR) performance and SO2-resistant ability of TiO2-SiO2-WO3 were greatly enhanced by the introduction of cerium. The catalyst containing 10% CeO2 showed the highest NO conversion in a wide temperature range and good N2 selectivity with broad operation temperature window at the gas hourly space velocity(GHSV) of 30000 h–1, which was a very promising catalyst for NOx abatement from diesel engine exhaust. The catalysts were characterized by X-ray diffraction(XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy(SEM-EDS), N2 adsorption-desorption(BET) and X-ray photoelectron spectroscopy(XPS). The characterization results showed that the bigger pore radius, higher surface atomic concentration and dispersion of Ce and the abundant adsorbed oxygen on the surface of catalyst contributed to the best NH3-SCR performance of CeO2/TiO2-SiO2-WO3 catalyst containing 10% CeO2. 展开更多
关键词 NH3-SCR NO cerium CeO2/TiO2-SiO2-WO3 monolith catalyst rare earths
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Preparation,characterization and catalytic properties of S_2O_82-/ZrO_2-CeO_2 solid superacid catalyst 认领 引用 被引量:34
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作者 樊国栋 沈茂 +1 位作者 张昭 贾发瑞 《Journal of Rare Earths》 SCIE EI CAS 2009年第3期437-442,共6页
A novel solid superacid catalyst S2O8^2-/ZrO2-CeO2 was prepared by a coprecipitation method and characterized by means of XRD FTIR, BET, TEM and DSC/TG analysis methods. The results indicated that incorporation of app... A novel solid superacid catalyst S2O8^2-/ZrO2-CeO2 was prepared by a coprecipitation method and characterized by means of XRD FTIR, BET, TEM and DSC/TG analysis methods. The results indicated that incorporation of appropriate amounts of Ce into the catalyst was beneficial to the formation of sole tetragonal ZrO2 and effectively prevented from the formation of monoclinic ZrO〉 and restrained the loss of sulfated species. XRD revealed the presence of tetragonal Ce0.16Zr0.84O2phase in the case of S2O8^2-/ZrO2-CeO2 calcined above 500 ℃. Catalytic activities of S2O8^2-/ZrO2-CeO2 for the esterification of lactic acid with n-butanol was studied. The results showed that the optimum conditions were as follows: calcination temperature of the catalyst 600 ℃, n(lactic acid):n(n-butyl alcohol)=1.0:3.0, w(S2O8^2-/ZrO2- CeO2)=12.0%, reaction temperature 145 ℃, and reaction time 2 h. The esterification efficiency of lactic acid was about 96.6%. 展开更多
关键词 solid superacid catalyst S2O8^2-/ZrO2-CeO2 n-butyl lactate esterification rare earths
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TiO_2-SiO_2/ZrO_2催化剂的制备及催化燃烧甲苯性能 认领 引用 被引量:8
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作者 刘媛 龙千明 +2 位作者 白云鹤 吕斯濠 范洪波 《化工进展》 CAS 北大核心 2010年第11期2090-2094,2102,共5页
以ZrO2为载体,制备出TiO2-SiO2/ZrO2催化剂,用XRD和SEM对其进行表征;并将催化剂用于甲苯的催化燃烧,探讨了温度、气流速率、进气浓度等因素对甲苯催化效率和反应产物CO、CO2选择性的影响。结果表明:催化剂中的TiO2呈锐钛矿晶型,催化剂... 以ZrO2为载体,制备出TiO2-SiO2/ZrO2催化剂,用XRD和SEM对其进行表征;并将催化剂用于甲苯的催化燃烧,探讨了温度、气流速率、进气浓度等因素对甲苯催化效率和反应产物CO、CO2选择性的影响。结果表明:催化剂中的TiO2呈锐钛矿晶型,催化剂颗粒成功负载于ZrO2表面;随着温度升高,甲苯催化效率增大,350℃时能达到最大值100%,CO2选择性随之增大,但CO选择性却减少;气流速率增大导致甲苯催化效率增大,CO选择性稍稍增大,而CO2选择性减小;进气浓度从25 mg/L增加到100 mg/L时,甲苯催化效率逐渐减小,CO2选择性减小,CO选择性稍有增大。 展开更多
关键词 TiO2-SiO2/ZrO2催化剂 催化燃烧 甲苯
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Highly selective CO methanation over amorphous Ni-Ru-B/ZrO2catalyst 认领 引用 被引量:15
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作者 Qi Hai Liu Xin Fa Dong Wei Ming Lin 《Chinese Chemical Letters》 SCIE CAS 2009年第8期889-892,共4页
Amorphous Ni-Ru-B/ZrO2 catalyst was prepared by the means of chemical reduction,and selective CO methanation as a strategy for CO removal in fuel processing applications was investigated over the amorphous Ni-Ru-B/ZrO... Amorphous Ni-Ru-B/ZrO2 catalyst was prepared by the means of chemical reduction,and selective CO methanation as a strategy for CO removal in fuel processing applications was investigated over the amorphous Ni-Ru-B/ZrO2 catalyst.The result showed that,at the temperature of 210-230℃,the catalyst was shown to be capable of reducing CO in a hydrogen-rich reformate to less than 10 ppm,while keeping the CO2conversion below 1.55%and the hydrogen consumption below 6.50%.?2009 Xin Fa Dong.Published by Elsevier B.V.on behalf of Chinese Chemical Society.All rights reserved. 展开更多
关键词 Selective methanation CO Amorphous Ni-Ru-B/ZrO2 catalyst
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Photocatalytic performance of TiO_2 catalysts modified by H_3PW12O40, ZrO_2 and CeO_2 认领 引用 被引量:5
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作者 CAI Tiejun LIAO Yuchao +3 位作者 PENG Zhenshan LONG Yunfei WEI Zongyuan DENG Qian 《Journal of Environmental Sciences》 SCIE EI CAS 2009年第7期997-1004,共8页
The binary composite photo-catalysts CeO2/ZiO2, ZrO2/ZiO2 and the ternary composite photo-catalysts H3PW12040-CeO2/TiO2, H3PW12O40-ZrO2/TiO2 were prepared by sol-gel method. The catalysts were characterized by thermog... The binary composite photo-catalysts CeO2/ZiO2, ZrO2/ZiO2 and the ternary composite photo-catalysts H3PW12040-CeO2/TiO2, H3PW12O40-ZrO2/TiO2 were prepared by sol-gel method. The catalysts were characterized by thermogravimetric-differential thermal analysis (TG-DTA), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The photocatalytic elimination of methanol was used as model reaction to evaluate the photocatalytic activity of the composite catalysts under ultraviolet light irradiation. The effects of doped content, activation temperature, time, initial concentration of methanol and gas flow rate on the catalytic activity were investigated. The results showed that after doping a certain amount of CeO2 and ZrO2, crystallization process of TiO2 was restrained, particles of catalysts are smaller and more uniform. Doping ZrO2 not only significantly improved the catalytic activity, but also increased thermal stability. Doping H3PW12O40 alSO enhanced the catalytic activity. The catalytic activities of binary and ternary composite photocatalysts were significantly higher than un-doped TiO2. The dynamics law of photocatalytic reaction over the binary CeO2/TiO2 and ZrO2/TiO2 catalysts has been studied. The activation energy 15.627 and 15.631 kJ/mol and pre-exponential factors 0.5176 and 0.9899 s^-1 over each corresponding catalyst were obtained. This reaction accords to the first order dynamics law. 展开更多
关键词 TiO2 H3PW12O40 ZrO2 CeO2 photocatalytic elimination of methanol
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Effect of ZrO_2 Crystalline Phase on the Performance of Ni-B/ZrO_2 Catalyst for the CO Selective Methanation 认领 引用 被引量:8
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作者 刘其海 廖列文 +1 位作者 刘自力 董新法 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第3期434-438,共5页
Amorphous Ni-B/ZrO2 catalysts were prepared by coprecipitation-chemical reduction with KBH4 aqueous solution,and various crystalline phase ZrO2(amorphous-ZrO2,tetragonal-ZrO2 and monoclinic-ZrO2) supported Ni-B cataly... Amorphous Ni-B/ZrO2 catalysts were prepared by coprecipitation-chemical reduction with KBH4 aqueous solution,and various crystalline phase ZrO2(amorphous-ZrO2,tetragonal-ZrO2 and monoclinic-ZrO2) supported Ni-B catalysts were obtained by thermal treatment in 5%H2-N2 stream at different temperature.The effect of ZrO2 polymorphs and the treatment temperature on the catalytic performance for the CO selective methanation were investigated,and the catalysts were characterized by N2 physisorption,Powder X-ray diffraction(XRD), Temperature-Programmed Desorption(CO-TPD and H2-TPD),and Differential Scanning Calorimeter(DSC).The treatment temperature affected strongly the crystalline structure of ZrO2,and the CO methanation activity and selectivity of the Ni-B/ZrO2 catalysts were significantly influenced by the crystalline phase of ZrO2.Of the three forms of ZrO2 polymorphs(amorphou-ZrO2,tetragonal-ZrO2 and monoclinic-ZrO2),the amorphous-ZrO2 supported nickle catalyst showed highest CO methanation activity,attributing in large part to the largest specific surface area and the optimum CO/H2 absorption intensity of the Ni-B/amorphous-ZrO2 catalyst. 展开更多
关键词 crystalline phase carbon monoxide selective methanation Ni-B/ZrO2 catalyst
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Effect of calcination temperature on structure and performance of Ni/TiO_2-SiO_2 catalyst for CO_2 reforming of methane 认领 引用 被引量:6
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作者 Sanbing Zhang Jiankang Wang Xiaolai Wang 《Journal of Natural Gas Chemistry》 2008年第2期179-183,共5页
The influence of calcination temperature on the structure and catalytic behavior of Ni/TiO2-SiO2 catalyst, for CO2 reforming of methane to synthesis gas under atmospheric pressure, was investigated. The results showed... The influence of calcination temperature on the structure and catalytic behavior of Ni/TiO2-SiO2 catalyst, for CO2 reforming of methane to synthesis gas under atmospheric pressure, was investigated. The results showed that the Ni/TiO2-SiO2 catalyst calcined at 700 ℃ had high and stable activity while the catalysts calcined at 550 and 850 ℃ had low and unstable activity. Depending on the calcination temperature, one, two, or three of the following Ni-containing species, NiO, Ni2.44Ti0.72Si0.07O4, and NiTiO3 were identified by combining the temperature programmed reduction (TPR) and X-ray diffraction (XRD) results. Their reducibility decreased in the sequence: NiO〉Ni2.44Ti0.72Si0.07O4〉NiTiO3. It suggests that high and stable activities observed over the Ni/TiO2-SiO2 catalyst calcined at 700 ~C were induced by the formation of Ni2.44Ti0.72Si0.07O4 and smaller NiO species crystallite size. 展开更多
关键词 Ni/TiO2-SiO2 catalyst sol-gel CO2 reforming methane
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Synergistic catalytic removals of NO,CO and HC over CeO_2 modified Mn-Mo-W-O_x/TiO_2-SiO_2 catalyst 认领 引用 被引量:15
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作者 Qijie Jin Yuesong Shen +3 位作者 Guorong Sui Xingjun Tao Youchun Pan Shemin Zhu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第2期148-155,共8页
A series of Mn-Mo-W-O_x/TiO_2-SiO_2 catalysts was modified with CeO_2 using an extrusion molding method. The catalytic activities of the obtained catalysts were tested for the synergistic catalytic removals of CO, NO ... A series of Mn-Mo-W-O_x/TiO_2-SiO_2 catalysts was modified with CeO_2 using an extrusion molding method. The catalytic activities of the obtained catalysts were tested for the synergistic catalytic removals of CO, NO and C_3H_8. The ratio of catalyst composition on catalytic activities for NH_3-SCR was optimized, which reveals that the molar ratio of Ti/Si was 9:1 and the catalyst containing 1.5 wt% CeO_2 and 12 wt% Mn-Mo-W-O_x exhibits the best catalytic performances. These samples were characterized by XRD, N_2-BET, Py-IR, NH_3-TPD, SEM/element mapping, H_2-TPR and XPS, respectively. Results show that the optimal catalyst exhibits more than 99% NO conversion, 86% CO conversion and 100% C_3H_8 conversion under GHSV of 5000 h^(-1). In addition, the GHSV has little influence on removal of NO when it is less than 15,000 h^(-1). Furthermore, the addition of CeO_2 will enhance the surface acidity, increase Mn^(4+)concentration and inhibit the grain growth, which are favorable for the excellent catalytic performance.Anyway,the 1.5 wt% CeO_2-12 wt% Mn-Mo-W-O_x/TiO_2-SiO_2 possesses outstanding redox properties,abundant acid sites and high Mn^(4+) concentration, which provide a guarantee for synergistic catalytic removal of CO, NO and HC. 展开更多
关键词 Mn-Mo-W-Ox/TiO2-SiO2 Cerium oxide additive Synergistic catalytic removal Nitrogen oxide Rare earths
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Sol-Gel法制备Al_2O_3-SiO_2-TiO_2-ZrO_2复合陶瓷膜的研究 认领 引用 被引量:4
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作者 徐晓虹 吴建锋 +1 位作者 白占良 张英 《中国陶瓷》 CAS 2003年第6期21-23,共3页
将Sol-Gel法应用于无机膜的制备,成功的研制出一种新型的膜面平整、膜厚均匀且无宏观缺陷的Al2O3-SiO2-TiO2-ZrO2复合陶瓷膜,复合膜含有γ-Al2O3、SiO2、TiO2、ZrO2和Al2SiO5等晶相,改变体系组成含量,晶相组成和含量随之变化,从而引起... 将Sol-Gel法应用于无机膜的制备,成功的研制出一种新型的膜面平整、膜厚均匀且无宏观缺陷的Al2O3-SiO2-TiO2-ZrO2复合陶瓷膜,复合膜含有γ-Al2O3、SiO2、TiO2、ZrO2和Al2SiO5等晶相,改变体系组成含量,晶相组成和含量随之变化,从而引起膜的显微结构的变化。利用XRD、SEM、AFM、EPMA等测试手段重点研究了膜的表面形貌和显微结构,并分析了添加剂、热处理方式等对膜的表面形貌和显微结构影响。 展开更多
关键词 溶胶—凝胶法 Al2O3—SiO2—TiO2—ZrO2复合陶瓷膜 表面形貌 显微结构
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Catalytic decomposition of CH_4 over Ni-Al_2O_3-SiO_2 catalysts:Influence of pretreatment conditions for the production of H_2 认领 引用 被引量:2
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作者 Jangam Ashok Gangadhara Raju +2 位作者 Padigapati Shiva Reddy Machiraju Subrahmanyam Akula Venugopal 《Journal of Natural Gas Chemistry》 2008年第2期113-119,共7页
This article reports the production of COx free hydrogen and carbon nanofibers by the catalytic decomposition of methane over Ni-Al2O3-SiO2 catalysts. The influence of reaction temperature, pretreatment temperature, a... This article reports the production of COx free hydrogen and carbon nanofibers by the catalytic decomposition of methane over Ni-Al2O3-SiO2 catalysts. The influence of reaction temperature, pretreatment temperature, and effect of reductive pretreatment on the decomposition of methane activity is investigated. The physico-chemical characteristics of fresh and deactivated samples were characterized using BET-SA, XRD, TPR, SEM/TEM, CHNS analyses and correlated with the methane decomposition results obtained. The Ni-Al-Si (4 : 0.5 : 1.5) catalyst reduced with hydrazine hydrate produced better H2 yields of ca. 1815 mol H2/mol Ni than the catalyst reduced with 5% H2/N2. 展开更多
关键词 in situ reduction Ni-Al2O3-SiO2 catalyst methane decomposition hydrogen production carbon nanofibers
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Selective Hydrogenation of Butyne-1,4-diol to Butane-1,4-diol over Ni/Al_2O_3-SiO_2 Catalysts 认领 引用 被引量:2
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作者 Fang Jie Zhuang Changjian +2 位作者 Meng Jipeng Cheng Lang Lu Jiangyin 《China Petroleum Processing & Petrochemical Technology》 CAS 2018年第4期20-28,共9页
Ni/Al_2O_3-SiO_2 catalysts were synthesized via one-step method employing SiO_2 as an additive for the selective hydrogenation of butyne-1,4-diol(B_3D) to butane-1,4-diol(B1D). The prepared catalysts were evaluated by... Ni/Al_2O_3-SiO_2 catalysts were synthesized via one-step method employing SiO_2 as an additive for the selective hydrogenation of butyne-1,4-diol(B_3D) to butane-1,4-diol(B1D). The prepared catalysts were evaluated by a series of characterization techniques including BET, XRD, SEM, EDX-mapping, TEM, H_2-TPR, XPS, NH_3-TPD and Py-FTIR. Compared to Ni/Al_2O_3 catalyst, the SiO_2-doped samples exhibited better B_3D conversion. SiO_2 could help to form a strong interaction between NiO with the support, which inhibited Ni agglomeration at high temperature, improved the Ni dispersion, and enhanced the hydrogenation activity. B_1D selectivity was mainly influenced by the quantity of Lewis acid sites in addition to the Ni dispersion. The catalyst with a silica loading of 6.4% demonstrated an excellent selectivity of 75.18%(by 13% higher than the contrastive Ni/Al_2O_3 catalyst), which was attributed to the larger amount of Lewis acid sites and the moderate interaction between NiO with the support, which could facilitate the nickel dispersion on a preferable surface area of 176.3 m^2/g of support. 展开更多
关键词 Ni/Al2O3-SiO2 catalysts butyne-1,4-diol butane-1,4-diol hydrogenation
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Selective catalytic methanation of CO in hydrogen-rich gases over Ni/ZrO_2 catalyst 认领 引用 被引量:26
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作者 Qihai Liu Xinfa Dong Xinman Mo Weiming Lin 《Journal of Natural Gas Chemistry》 2008年第3期268-272,共5页
Ni/ZrO2 catalysts were prepared by the incipient-wetness impregnation method and were investigated in activity and selectivity for the selective catalytic methanation of CO in hydrogen-rich gases with more than 20 vol... Ni/ZrO2 catalysts were prepared by the incipient-wetness impregnation method and were investigated in activity and selectivity for the selective catalytic methanation of CO in hydrogen-rich gases with more than 20 vol% CO2. The result showed that Ni loadings significantly influenced the performance of Ni/ZrO2 catalyst. The 1.6 wt% Ni loading catalyst exhibited the highest catalytic activity among all the catalysts in the selective methanation of CO in hydrogen-rich gas. The outlet concentration of CO was less than 20 ppm with the hydrogen consumption below 7%, at a gas-hourly-space velocity as high as 10000 h-1 and a temperature range of 260 °C to 280 °C. The X-ray diffraction (XRD) and temperature programmed reduction (TPR) measurements showed that NiO was dispersed thoroughly on the surface of ZrO2 support if Ni loading was under 1.6 wt%. When Ni loading was increased to 3 wt% or above, the free bulk NiO species began to assemble, which was not favorable to increase the selectivity of the catalyst. 展开更多
关键词 selective methanation CO removal Ni/ZrO2 catalyst hydrogen-rich gases fuel cell
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Al_2O_3-SiO_2-TiO_2-ZrO_2复合陶瓷膜的制备与表征 认领 引用 被引量:1
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作者 徐晓虹 张英 +1 位作者 吴建锋 白占良 《硅酸盐通报》 CAS 2003年第5期28-31,共4页
采用Sol-Gel法制备出掺杂SiO2 ,TiO2 及ZrO2 改性的γ -Al2 O3 膜 ,并通过SEM ,EPMA ,AFM等测试手段对膜结构和性能进行表征。探讨了制膜工艺条件对膜性能及结构的影响。制备的Al2 O3 复合膜膜厚为 1~ 2 μm ,结构均匀无缺陷。
关键词 Al2O3 SiO2 TiO2 ZrO2 复合陶瓷膜 制备 表征 膜结构 性能 掺杂 γ-Al2O3膜
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Study on the Nanosized Amorphous Ru-Fe-B/ZrO_2 Alloy Catalyst for Benzene Selective Hydrogenation to Cyclohexene 认领 引用 被引量:14
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作者 Shouchang Liu Zhongyi Liu Shuhui Zhao Yongmei Wu Zheng Wang Peng Yuan 《Journal of Natural Gas Chemistry》 2006年第4期319-326,共8页
A novel nanosized amorphous Ru-Fe-B/ZrO2 alloy catalyst for benzene selective hydrogenation to cyclohexene was investigated. The superior properties of this catalyst were attributed to the combination of the nanosize ... A novel nanosized amorphous Ru-Fe-B/ZrO2 alloy catalyst for benzene selective hydrogenation to cyclohexene was investigated. The superior properties of this catalyst were attributed to the combination of the nanosize and the amorphous character as well as to its textural character. In addition, the concentration of zinc ions, the content of ZrO2 in the slurry, and the pretreatment of the catalyst were found to be effective in improving the activity and the selectivity of the catalyst. 展开更多
关键词 Ru-Fe-B/ZrO2 amorphous catalyst benzene selective hydrogenation cyclohexene
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The Effect of Platinum on Stability of the B_2O_3/TiO_2-ZrO_2 Catalyst for Beckmann Rearrangement of Cyclohexanone Oxime 认领 引用
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作者 Dong Sen MAO Guan Zhong LU 《Chinese Chemical Letters》 SCIE CAS 2006年第8期1025-1028,共4页
The addition of platinum over the B2O3/TiO2-ZrO2 remarkably enhanced its catalytic stability in the vapor phase Beckmann rearrangement of cyclohexanone oxime under the carder gas of H2. The content of coke deposited o... The addition of platinum over the B2O3/TiO2-ZrO2 remarkably enhanced its catalytic stability in the vapor phase Beckmann rearrangement of cyclohexanone oxime under the carder gas of H2. The content of coke deposited on catalyst surface was decreased from 1.92% over the B2O3/TiO2-ZrO2 to 1.14% over the platinum promoted B2O3/TiO2-ZrO2 after reaction of six hours. This result indicates that the platinum added on the B2O3/TiO2-ZrO2 catalyst plays an important role in reducing the coke formation on the catalyst surface. 展开更多
关键词 Cyclohexanone oxime vapor-phase Beckmann rearrangement ε-caprolactam B2O3/TiO2-ZrO2 catalyst platinum.
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Preparation of Al_2O_3-SiO_2-TiO_2-ZrO_2 Composite Ceramic Membranes by Sol-Gel Method 认领 引用
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作者 吴建锋 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第1期42-45,共4页
Al 2O 3-SiO 2-TiO 2-ZrO 2 supported membranes were prepar ed by Sol-Gel method. These composite ceramic membranes are level, even and no macro crack. There exist several crystalline phases such as Al 2O 3, TiO 2(a nat... Al 2O 3-SiO 2-TiO 2-ZrO 2 supported membranes were prepar ed by Sol-Gel method. These composite ceramic membranes are level, even and no macro crack. There exist several crystalline phases such as Al 2O 3, TiO 2(a natase), Al 2SiO 5, and ZrO 2 in these membranes. Changing the molar ratio of Al∶Si∶Ti∶Zr,the kinds and content of crystal phases of composite membranes could be different, which may lead to a variety of microstructure of membranes. The surface nanoscale topography and microstructure of membranes were investiga ted by XRD,SEM,AFM,EPMA. The effects of additives and heat treatments on the sur face nanoscale topography and microstructure of composite ceramic membranes were also analyzed. 展开更多
关键词 sol-gel method Al 2O 3-SiO 2-TiO 2-ZrO 2 composite ceramic membranes surface nanoscale topography microstructure
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Catalytic combustion of methane over nano ZrO_2-supported copper-based catalysts 认领 引用 被引量:7
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作者 Fen Fen Qua Wei Chu +2 位作者 Li Min Shi Mu Hua Chen Jin Yan Hu 《Chinese Chemical Letters》 SCIE CAS 2007年第8期993-996,共4页
The nano ZrO2-supported copper-based catalysts for methane combustion were investigated by means of N2 adsorption, TEM, XRD, H2-TPR techniques and the test of methane oxidation. Two kinds of ZrO2 were used as support,... The nano ZrO2-supported copper-based catalysts for methane combustion were investigated by means of N2 adsorption, TEM, XRD, H2-TPR techniques and the test of methane oxidation. Two kinds of ZrO2 were used as support, one (ZrO2-1) was obtained from the commercial ZrO2 and the other (ZrO2-2) was issued from the thermal decomposition of zirconium nitrate. It was found that the CuO/ZrO2-2 catalyst was more active than CuO/ZrO2-1. N2 adsorption, H2-TPR and XRD measurements showed that larger surface area, better reduction property, presence of tetragonal ZrO2 and higher dispersion of active component for CuO/ZrO2-2 than that of CuO/ZrO2-1. These factors could be the dominating reasons for its higher activity for methane combustion. 展开更多
关键词 Nano ZrO2 Copper-based catalysts Catalytic combustion Methane
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ZrO_2-modified Ni/LaAl11O18 catalyst for CO methanation: Effects of catalyst structure on catalytic performance 认领 引用 被引量:4
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作者 Hongmei Ai Hongyuan Yang +3 位作者 Qing Liu Guoming Zhao Jing Yang Fangna Gu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期297-308,共12页
We report Ni/LaHA@ZrO2catalysts prepared by a facile modified successive adsorption and reaction method for CO methanation.N2adsorption,X‐ray diffraction,transmission electron microscopy,scanning electron microscopy,... We report Ni/LaHA@ZrO2catalysts prepared by a facile modified successive adsorption and reaction method for CO methanation.N2adsorption,X‐ray diffraction,transmission electron microscopy,scanning electron microscopy,thermogravimetric analysis,H2temperature‐programmed reduction,H2temperature‐programmed desorption,X‐ray photoelectron spectroscopy,thermogravimetric analysis,and inductively coupled plasma atomic emission spectrometry were used to characterize the samples.The results indicated that the ZrO2nanoparticles were distributed over the surface of the Ni/LaHA@ZrO2catalyst and even partially covered some Ni particles,resulting in the coating exerting a confinement effect.The excess ZrO2had an adverse effect on the enhancement of CO conversion because of the coverage of the surface Ni particles;however,the Ni/LaHA@ZrO2catalyst displayed much higher CH4selectivity than Ni/LaHA because of the activation of the byproduct CO2molecules by ZrO2species.Therefore,even though20Ni/LaHA@ZrO2‐5exhibited similar CO conversion as20Ni/LaHA,the use of the former resulted in a higher CH4yield than the use of the latter.A107‐h‐lifetime test revealed that the Ni/LaHA@ZrO2catalyst was highly stable with superior anti‐sintering and anti‐coking properties because of its coating structure and the promoter effect of ZrO2. 展开更多
关键词 Lanthanum hexaaluminate ZrO2 Nickel catalyst Coating structure CO methanation
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Comparative study of fluidized-bed and fixed-bed reactor for syngas methanation over Ni-W/TiO_2-SiO_2 catalyst 认领 引用 被引量:9
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作者 Bo Liu Shengfu Ji 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第5期740-746,共7页
In this work,syngas methanation over Ni-W/TiO2-SiO2catalyst was studied in a fluidized-bed reactor(FBR)and its performance was compared with a fixed-bed reactor(FIXBR).The effects of main operating variables including... In this work,syngas methanation over Ni-W/TiO2-SiO2catalyst was studied in a fluidized-bed reactor(FBR)and its performance was compared with a fixed-bed reactor(FIXBR).The effects of main operating variables including feedstock gases space velocity,coke content,bed temperature and sulfur-tolerant stability of 100 h life were investigated.The structure of the catalysts was characterized by XRD,N2adsorptiondesorption and TEM.It is found that under same space velocity from 5000 h 1to 25000 h 1FBR gave a higher CH4yield,lower coke content,and lower bed temperature than those obtained in FIXBR.Ni-W/TiO2-SiO2catalyst possessed excellent sulfur-tolerant stability on the feedstock gases less than 500 ppm H2S in FBR.The carbon deposits formed on the spent catalyst were in the form of carbon fibers in FBR,while in the form of dense accumulation distribution appearance in FIXBR. 展开更多
关键词 syngas methanation Ni-W/TiO2-SiO2catalyst fluidized bed fixed bed
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Selective CO methanation over amorphous Ni-Ru-B/ZrO_2 catalyst for hydrogen-rich gas purification 认领 引用 被引量:6
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作者 Qihai Liu Zili Liu +1 位作者 LieWen Liao Xinfa Dong 《Journal of Natural Gas Chemistry》 2010年第5期497-502,共6页
Amorphous Ni-Ru-B/ZrO2 catalysts were prepared by chemical reduction method. The effects of Ni-Ru-B loading and Ru/Ni mole ratio on the catalytic performance for selective CO methanation from reformed fuel were studie... Amorphous Ni-Ru-B/ZrO2 catalysts were prepared by chemical reduction method. The effects of Ni-Ru-B loading and Ru/Ni mole ratio on the catalytic performance for selective CO methanation from reformed fuel were studied, and the catalysts were characterized by BET, ICP, XRD and TPD. The results showed that Ru strongly affected the catalytic activity and selectivity by increasing the thermal stability of amorphous structure, promoting the dispersion of the catalyst particle, and intensifying the CO adsorption. For the catalysts with Ru/Ni mole ratio under 0.15, the CO methanation conversion and selectivity increased significantly with the increasing Ru/Ni mole ratio. Among all the catalysts investigated, the 30 wt% Ni-Ru-B loading amorphous Ni61Ru9B30/ZrO2 catalyst with 0.15 Ru/Ni mole ratio presented the best catalytic performance, over which higher than 99.9% of CO conversion was obtained in the temperature range of 230℃-250℃, and the CO2 conversion was kept under the level of 0.9%. 展开更多
关键词 selective methanation CO hydrogen purification amorphous Ni-Ru-B/ZrO2 catalyst
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