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Fe2O3含量对青花色料呈色的影响
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作者 李小龙 马岚 +3 位作者 李勋 胡其国 邱辉辉 包启富 《佛山陶瓷》 CAS 2024年第7期36-39,共4页
实验以二氧化三铁、氧化钴、氧化锰、釉果为主要原料,采用单因素实验法,探究了青花色料中Fe2O3/CoO对青花瓷色度值、微观结构、晶相组成的影响。实验结果表明,随着青花色料配方中Fe2O3/CoO比值增大,青花瓷着色区域表面析出大量的1~3μm... 实验以二氧化三铁、氧化钴、氧化锰、釉果为主要原料,采用单因素实验法,探究了青花色料中Fe2O3/CoO对青花瓷色度值、微观结构、晶相组成的影响。实验结果表明,随着青花色料配方中Fe2O3/CoO比值增大,青花瓷着色区域表面析出大量的1~3μm磁铁矿晶体并且发育越来越好,使得青花瓷呈现黑色调增强蓝色调减弱的现象。 展开更多
关键词 fe2o3/Coo 青花色料 磁铁矿
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Fe、La掺杂和氧缺陷对CeO_(2)表面吸附As_(2)O_(3)的密度泛函理论研究
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作者 卢鲲鹏 张凯华 张锴 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第8期1149-1161,共13页
采用密度泛函理论研究了As_(2)O_(3)(g)在Fe、La掺杂CeO_(2)(110)表面及氧缺陷LaCeO(110)表面的吸附行为,探索了LaCeO表面砷吸附能力显著高于FeCeO表面的主要原因。结果表明,As_(2)O_(3)(g)的吸附效果与吸附位点数量、吸附能、键长和电... 采用密度泛函理论研究了As_(2)O_(3)(g)在Fe、La掺杂CeO_(2)(110)表面及氧缺陷LaCeO(110)表面的吸附行为,探索了LaCeO表面砷吸附能力显著高于FeCeO表面的主要原因。结果表明,As_(2)O_(3)(g)的吸附效果与吸附位点数量、吸附能、键长和电荷转移密切相关。纯CeO_(2)表面的吸附主要为化学吸附,吸附能绝对值大于−4.22 eV,电荷转移量为(−0.19)−(−0.31)e,As_(2)O_(3)得到电荷带负电,起表面受主作用,因此吸附量较小。FeCeO(110)表面新增Fe顶位和Bridge-2桥位两个吸附位,其中,Fe顶位为化学吸附,Fe掺杂改变了FeCeO表面电子分布和晶格结构,但并未改变As_(2)O_(3)与FeCeO之间的电荷转移方向,因此,As_(2)O_(3)仍呈负离子形式吸附。LaCeO(110)表面新增了三个吸附位:La顶位、Bridge-3桥位和Hollow-2空位,La掺杂改变了As_(2)O_(3)与LaCeO之间的电荷转移方向,使得As_(2)O_(3)失电子呈正离子吸附,起表面施主作用,因此,吸附能力增强。无O_(2)环境下,单一O缺陷LaCeO(110)表面吸附能力低于完整LaCeO表面;有O_(2)环境下,O缺陷有利于As_(2)O_(3)的吸附。 展开更多
关键词 密度泛函理论 二氧化铈 fe、La掺杂 As_(2)o_(3)吸附 o缺陷
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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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Fe和Cu分子筛催化剂同时催化NO_(x)还原和N_(2)O分解
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作者 司庆宇 樊星 +2 位作者 张玮航 苗静文 刘若雯 《中国环境科学》 EI CAS CSCD 北大核心 2024年第9期4826-4834,共9页
采用离子交换法制备了Fe-Beta和Cu-SSZ-13催化剂并采用不同混合方式制备了复合催化剂,考察了催化剂同时催化NO_(x)还原和N_(2)O分解的性能.以实现NO_(x)和N_(2)O同时高效去除、拓宽活性温度窗口为目标,优选出了上Fe下Cu分层填充、Fe-Bet... 采用离子交换法制备了Fe-Beta和Cu-SSZ-13催化剂并采用不同混合方式制备了复合催化剂,考察了催化剂同时催化NO_(x)还原和N_(2)O分解的性能.以实现NO_(x)和N_(2)O同时高效去除、拓宽活性温度窗口为目标,优选出了上Fe下Cu分层填充、Fe-Beta和Cu-SSZ-13质量比为4:1的Fe_(0.4)Cu_(0.1)催化剂,进一步考察了进气组成对NO_(x)、N_(2)O和NH_(3)转化率的影响,并采用N_(2)吸脱附、XRD、NH_(3)-TPD、UV-Vis DRS和H_(2)-TPR等手段对催化剂理化特性进行了表征.结果表明,Cu-SSZ-13和Fe-Beta分别具有更优的催化NO_(x)还原和N_(2)O分解性能.采用Fe_(0.4)Cu_(0.1)催化剂、[NH_(3)]/[NO_(x)]为1时考察的温度范围内NH_(3)仅还原NO_(x),而N_(2)O通过分解去除,450℃时NO_(x)和N_(2)O转化率分别为93.4%和100%.高温(>350℃)下NH_(3)被O_(2)氧化导致NO_(x)转化率随温度升高而降低;高温(≥350℃)下N_(2)O分解形成的氧物种可使NO_(x)在进气中无O_(2)条件下实现高效还原.进气中含2%H_(2)O对高温(450℃)下Fe_(0.4)Cu_(0.1)表面NO_(x)的还原和NH_(3)的氧化无显著影响,但对N_(2)O的转化存在一定的可逆抑制作用.Cu-SSZ-13表面存在大量孤立的Cu^(2+)离子,可为NH_(3)-SCR反应提供充足的活性中心.Fe-Beta表面同时存在能够催化NO氧化的孤立Fe^(3+)离子和催化N_(2)O分解的Fe_(x)O_(y)物种.采用上Fe下Cu分层填充的混合方式时Fe-Beta表面NO氧化过程会消耗N_(2)O分解形成的氧物种,从而有利于低温(≤450℃)下N_(2)O的转化.但由于N_(2)O分解的温度范围内NO_(x)转化率本身较高,NO氧化对于脱硝的促进作用不显著. 展开更多
关键词 No_(x)还原 N_(2)o分解 fe-Beta Cu-SSZ-13 复合催化剂
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Polygonal mesopores microflower catalysts for the catalytic oxidation of 2-nitro-4-methylsulfonyltoluene to 2-nitro-4-methylsulfonylbenzoic acid in a continuous-flow microreactor
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作者 Jianzhi Wang Xugen Li +6 位作者 Cheng Zhang Yuan Pu Jiawu Liu Jie Liu Yanping Liu Xiao Lin Faquan Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期212-221,共10页
The development of efficient systems for the catalytic oxidation of 2-nitro-4-methylsulfonyltoluene(NMST)to 2-nitro-4-methylsulfonyl benzoic acid(NMSBA)with atmospheric air or molecular oxygen in alkaline medium prese... The development of efficient systems for the catalytic oxidation of 2-nitro-4-methylsulfonyltoluene(NMST)to 2-nitro-4-methylsulfonyl benzoic acid(NMSBA)with atmospheric air or molecular oxygen in alkaline medium presents a significant challenge for the chemical industry.Here,we report the synthesis of FeOOH/Fe_(3)O_(4)/metal-organic framework(MOF)polygonal mesopores microflower templated from a MIL-88B(Fe)at room temperature,which exposes polygonal mesopores with atomistic edge steps and lattice defects.The obtained FeOOH/Fe_(3)O_(4)/MOF catalyst was adsorbed onto glass beads and then introduced into the microchannel reactor.In the alkaline environment,oxygen was used as oxidant to catalyze the oxidation of NMST to NMSBA,showing impressive performance.This sustainable system utilizes oxygen as a clean oxidant in an inexpensive and environmentally friendly NaOH/methanol mixture.The position and type of substituent critically affect the products.Additionally,this sustainable protocol enabled gram-scale preparation of carboxylic acid and benzyl alcohol derivatives with high chemoselectivities.Finally,the reactions can be conducted in a pressure reactor,which can conserve oxygen and prevent solvent loss.Moreover,compared with the traditional batch reactor,the self-built microchannel reactor can accelerate the reaction rate,shorten the reaction time,and enhance the selectivity of catalytic oxidation reactions.This approach contributes to environmental protection and holds potential for industrial applications. 展开更多
关键词 2-nitro-4-methylsulfonylbenzoic 2-nitro-4-methylsulfonyltoluene feooH/fe3o4/MoF catalyst MICRoREACToR oxidation
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催化剂中Rh含量对NH_(3)及N_(2)O生成量影响研究
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作者 李大成 刘志敏 +3 位作者 杨兰 刘世成 王燕 孙创 《河南化工》 CAS 2024年第7期8-12,共5页
研究了不同Rh含量的三效催化剂对CO和NO_(x)的起燃性能,并对反应过程中副产物NH_(3)以及N_(2)O的生成规律进行研究。实验通过浸渍法制备得到不同Rh含量的Rh-Pd/Ce_(x)Zr_(1-x)O_(2)+La-Al_(2)O_(3)催化剂,采用一套专用多路固定床连续流... 研究了不同Rh含量的三效催化剂对CO和NO_(x)的起燃性能,并对反应过程中副产物NH_(3)以及N_(2)O的生成规律进行研究。实验通过浸渍法制备得到不同Rh含量的Rh-Pd/Ce_(x)Zr_(1-x)O_(2)+La-Al_(2)O_(3)催化剂,采用一套专用多路固定床连续流动模拟气反应器对其性能进行评价。研究结果表明:不同Rh负载量表现出不同的N_(2)选择性,随着Rh用量的增加NO_(x)的转化性能提升。总体来看,低Rh用量的催化剂产生更多的N_(2)O和NH_(3)副产物,而随着Rh用量的增加其N_(2)选择性也增加。当温度达到400℃时,Rh用量≥0.141 g/L的催化剂基本没有N_(2)O生成,Rh用量≥0.283 g/L基本没有N_(2)O和NH_(3)生成。该研究对于优化三效催化剂中Rh配比以提升N_(2)选择性具有借鉴意义,并对于设计满足未来国Ⅶ排放标准的三效催化剂具有重要的指导意义。 展开更多
关键词 三效催化剂 Rh用量 NH_(3)生成 N_(2)o生成 N_(2)选择性
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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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Fe^(2+)与Fe^(3+)对anammox体系中N_(2)O排放的影响
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作者 杨余涤非 沈雁文 朱南文 《环境科学与技术》 CAS CSCD 北大核心 2023年第11期11-19,共9页
有研究表明,适量Fe^(2+)与Fe^(3+)能够促进anammox菌体代谢,但对于菌体N_(2)O产量的影响仍未可知。该文以批次实验的形式探究anammox在不同浓度Fe^(2+)与Fe^(3+)浓度下的N_(2)O产量,并分析其微生物组学和功能基因变化。结果表明,加入Fe^... 有研究表明,适量Fe^(2+)与Fe^(3+)能够促进anammox菌体代谢,但对于菌体N_(2)O产量的影响仍未可知。该文以批次实验的形式探究anammox在不同浓度Fe^(2+)与Fe^(3+)浓度下的N_(2)O产量,并分析其微生物组学和功能基因变化。结果表明,加入Fe^(2+)的组别中N_(2)O排放量在20 mg/L Fe^(2+)时最高(0.29 mg/L),30 mg/L Fe^(2+)时下降47.01%;加入Fe^(3+)的组别中N_(2)O排放量随Fe^(3+)浓度递增,30 mg/L Fe^(3+)时N_(2)O最高排放量为0.17 mg/L。微生物群落多样性分析表明,5 mg/L Fe^(2+)和Fe^(3+)能刺激Candidatus Kuenenia的生长,然而反硝化菌Denitratisoma和Limnobacter随Fe^(2+)和Fe^(3+)浓度的提高而增加。功能基因分析表明,N_(2)O的释放与硝化途径、DNRA途径、反硝化途径以及anammox途径中的功能基因有关,并与基因norB、nirD、hcp呈显著正相关(P<0.05)。该文阐述了Fe^(2+)与Fe^(3+)对anammox体系N_(2)O排放的影响,可为anammox工艺中的N_(2)O控制提供参考。 展开更多
关键词 fe^(3+) fe^(2+) N_(2)o 厌氧氨氧化 微生物群落结构 功能基因
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室温下锰掺杂Y(OH)_(3)/Fe_(2)O_(3)复合材料对甲醛气体传感特性的研究
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作者 阿尔孜古・许克尔 李锦 《新疆大学学报(自然科学版)(中英文)》 CAS 2023年第1期61-68,共8页
采用水热法合成了一种锰掺杂Y(OH)_(3)/Fe_(2)O_(3)的高性能甲醛传感器.通过XRD、SEM、EDS和XPS分析了锰掺杂Y(OH)_(3)/Fe_(2)O_(3)复合材料的结构、形貌以及组成成分.通过表征结果发现,锰元素掺杂Y(OH)_(3)/Fe_(2)O_(3)使得Y(OH)_(3)/F... 采用水热法合成了一种锰掺杂Y(OH)_(3)/Fe_(2)O_(3)的高性能甲醛传感器.通过XRD、SEM、EDS和XPS分析了锰掺杂Y(OH)_(3)/Fe_(2)O_(3)复合材料的结构、形貌以及组成成分.通过表征结果发现,锰元素掺杂Y(OH)_(3)/Fe_(2)O_(3)使得Y(OH)_(3)/Fe_(2)O_(3)颗粒分布更加均匀,表面氧空位缺陷增多,有可能提供更多的活性位点来吸附甲醛气体,增强了锰掺杂Y(OH)_(3)/Fe_(2)O_(3)的气敏性能.气敏测试结果表明:基于锰掺杂Y(OH)_(3)/Fe_(2)O_(3)复合材料的甲醛传感器相比Y(OH)_(3)/Fe_(2)O_(3)不仅具有高灵敏度和良好的选择性,而且能够在室温下表现出快速的响应和恢复特性.最后讨论了锰掺杂Y(OH)_(3)/Fe_(2)O_(3)对甲醛气敏性增强的传感机制,进一步说明基于锰掺杂Y(OH)_(3)/Fe_(2)O_(3)复合材料的甲醛传感器在实际应用中的潜在价值. 展开更多
关键词 锰掺杂Y(oH)3/fe2o3 室温 快速响应 气敏传感性能
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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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新型Zn-MOFs的合成及对水中Fe^(3+),Cr_(2)O_(7)^(2-)离子的荧光传感
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作者 王晓丽 王爱荣 +1 位作者 史忠丰 李家明 《广州化工》 CAS 2023年第5期61-66,共6页
通过水热法合成一种新型Zn-MOFs:[Zn(qs)(bmboxy)_(1.5)(H_(2)O)_(1.5)]n(CP1)(H_(2)qs=8-羟基喹啉-5-磺酸;bmboxy=1-(4-苯并咪唑)苯醚),采用X-射线单晶衍射、红外等表征。CP 1属三斜晶系,空间群为P 2/c,Zn(II)离子为五配位,形成一个畸... 通过水热法合成一种新型Zn-MOFs:[Zn(qs)(bmboxy)_(1.5)(H_(2)O)_(1.5)]n(CP1)(H_(2)qs=8-羟基喹啉-5-磺酸;bmboxy=1-(4-苯并咪唑)苯醚),采用X-射线单晶衍射、红外等表征。CP 1属三斜晶系,空间群为P 2/c,Zn(II)离子为五配位,形成一个畸变的三角双锥构型,bmboxy配体采取μ2桥联方式连接两个相邻的Zn(II)离子,呈二维网络结构。固体CP 1表现出较强的荧光性能,归因于配体内部π*-π的电子跃迁所致。实验表明,通过荧光猝灭机制,CP 1可以作为检测水溶液中Fe^(3+),Cr_(2)O_(2)-7离子的荧光传感材料,其检测限分别为1.67×10^(-4)M和2.04×10^(-5)M。 展开更多
关键词 金属有机框架 晶体结构 fe^(3+) Cr_(2)o^(2-)_(7) 荧光传感
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Fe_3O_4@UiO-66-NH_2 core–shell nanohybrid as stable heterogeneous catalyst for Knoevenagel condensation 被引量:6
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作者 张艳梅 戴田霖 +3 位作者 张帆 张静 储刚 权春善 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第12期2106-2113,共8页
separation is an attractive alternative to filtration or centrifugation for separating solid catalysts from a liquid phase, Here, core-shell Fe3O4@UiO-66-NH2 nanohybrids with well-defined structures were constructed b... separation is an attractive alternative to filtration or centrifugation for separating solid catalysts from a liquid phase, Here, core-shell Fe3O4@UiO-66-NH2 nanohybrids with well-defined structures were constructed by dispersing magnets in a dimethylformamide (DMF) solution con- taining two metal-organic framework (MOF) precursors, namely ZrCI4 and 2-aminobenzenetricar- boxylic acid. This method is simpler and more efficient than previously reported step-by-step method in which magnets were consecutively dispersed in DMF solutions each containing one MOF precursor, and the obtained Fe304@UiO-66-NH2 with three assembly cycles has a higher degree of crystallinity and porosiW. The core-shell Fe3O4@UiO-66-NH2 is highly active and selective in Knoevenagel condensations because of the bifunctionality of UiO-66-NH2 and better mass transfer in the nano-sized shells. It also has good recycling stability, and can be recovered magnetically and reused at least four times without significant loss of catalytic activity and framework integrity. The effects of substitution on the reactivity of benzaldehyde and of substrate size were also investigated. 展开更多
关键词 Metal-organic framework Uio-66-NH2 fe3o4 Heterogeneous catalyst Knoevenagel condensation Magnetic separation
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Effects of ZrO_2 on the Performance of CuO-ZnO-Al_2O_3/HZSM-5 Catalyst for Dimethyl Ether Synthesis from CO_2 Hydrogenation 被引量:13
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作者 Yanqiao Zhao Jixiang Chen Jiyan Zhang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第4期389-392,共4页
A series of composite catalysts were prepared by the wet mixing method, and the mass ratio of CuO-ZnO-Al2O3-ZrO2 component to HZSM-5 zeolite (molar ratio of SiO2 to Al2O3 being 25) was 2:1. The CuO-ZnO-Al2O3-ZrO2 ... A series of composite catalysts were prepared by the wet mixing method, and the mass ratio of CuO-ZnO-Al2O3-ZrO2 component to HZSM-5 zeolite (molar ratio of SiO2 to Al2O3 being 25) was 2:1. The CuO-ZnO-Al2O3-ZrO2 (CuO/ZnO/Al2O3=3/6/1 by weight) component was prepared by a modified 'two-step' co-precipitation method. The effects of ZrO2 on the performance of CuO-ZnO-Al2O3/HZSMo5 catalyst for dimethyl ether synthesis from CO2 hydrogenation were investigated. It was found that ZrO2 improved the properties of CuO-ZnO-Al2O3/HZSM-5 as a structural promoter. 展开更多
关键词 Cuo-Zno-Al2o3/HZSM-5 catalyst Co2 hydrogenation dimethyl ether ZIRCoNIA
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Preparation and properties of a nano TiO_2/Fe_3O_4 composite superparamagnetic photocatalyst 被引量:8
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作者 LI Yuxiang ZHANG Mei +1 位作者 GUO Min WANG Xidong 《Rare Metals》 SCIE EI CAS CSCD 2009年第5期423-427,共5页
Nano TiO2/Fe3O4 composite particles with different molar ratios of TiO2 to Fe3O4 were prepared via sol-gel method. X-ray diffraction, transmission electron microscopy, and vibration sample magnetometry were used to ch... Nano TiO2/Fe3O4 composite particles with different molar ratios of TiO2 to Fe3O4 were prepared via sol-gel method. X-ray diffraction, transmission electron microscopy, and vibration sample magnetometry were used to characterize the TiO2/Fe3O4 particles. The photocatalytic activity of the particles was tested by degrading methyl blue solution under UV illumination (254 nm). The results indicate that with the content of TiO2 increasing, the photocatalytic activity of the composite particles enhances, while the magnetism of the particles decreases. When the molar ratio of TiO2 to Fe3O4 is about 8, both the photocatalytic activity and magnetism of the TiO2/Fe3O4 particles are relatively high, and their photocatalytic activity remains well after repeated use. 展开更多
关键词 PHoToCATALYSIS SUPERPARAMAGNETISM sol-gel method Tio2 fe3o4
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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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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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Preparation and characterization of Fe_2O_3-CeO_2-TiO_2/γ-Al_2O_3 catalyst for degradation dye wastewater 被引量:5
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作者 LIU Yan SUN De-zhi CHENG Lin LI Yan-ping 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1189-1192,共4页
In order to develop a catalyst with high activity for catalytic wet oxidation (CWO) process at room temperature and atmospheric pressure, Fe2O3-CeO2-TiO2/γ-Al2O3 catalyst was prepared by consecutive impregnation me... In order to develop a catalyst with high activity for catalytic wet oxidation (CWO) process at room temperature and atmospheric pressure, Fe2O3-CeO2-TiO2/γ-Al2O3 catalyst was prepared by consecutive impregnation method and the prepared parameters were optimized. The structure of the catalyst was characterized by BET, XRF, SEM and XPS technologies, and the actual wastewater was used to investigate the catalytic activity of Fe2O3-CeO2-TiO2/γ-Al2O3 in CWO process. The experimental results showed that the prepared catalyst exhibited good catalytic activity when the doping amount of Ti was 1.0 wt% (the weight ratio of Ti to carriers), and the middle product, Fe2O3-CeO2-TiO2/γ-Al2O3, was calcined in 450℃ for 2 h. The CWO experiment for treating actual dye wastewater indicated that the COD, color and TOC of actual wastewater were decreased by 62.23%, 50.12% and 41.26% in 3 h, respectively, and the ratio of BOD5/COD was increased from 0.19 to 0.30. 展开更多
关键词 catalytic wet oxidation (CWo fe2o3-Ceo2-Tio2/γ-Al2o3 catalyst dye wastewater treatment
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Sodium dodecyl sulfate-decorated MOF-derived porous Fe2O3 nanoparticles: High performance, recyclable photocatalysts for fuel denitrification 被引量:4
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作者 Ruowen Liang Zhiyu Liang +5 位作者 Feng Chen Danhua Xie Yanling Wu Xuxu Wang Guiyang Yan Ling Wu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第1期188-199,共12页
Magnetically recyclable porous sodium dodecyl sulfate(SDS)/Fe2O3 hybrids,which combine the porous structure of Fe2O3 and hydrophobicity of SDS,have been successfully synthesized for the first time.Porous Fe2O3 has bee... Magnetically recyclable porous sodium dodecyl sulfate(SDS)/Fe2O3 hybrids,which combine the porous structure of Fe2O3 and hydrophobicity of SDS,have been successfully synthesized for the first time.Porous Fe2O3 has been first pyrolyzed from MIL-100(Fe)using a simple two-step calcination route.Then,the obtained porous Fe2O3 nanoparticles have been self-assembled with SDS molecules and yielded hydrophobic SDS/Fe2O3 hybrids.The porous SDS/Fe2O3 hybrids have been demonstrated to be highly efficient for the denitrification of pyridine under visible light irradiation.The pyridine removal ratio has reached values as high as 100%after irradiation for 240 min.Combining the results of a series of experimental measurements,it was concluded that the superior photocatalytic performance of SDS/Fe2O3 hybrids could be attributed to(i)the fast electron transport owing to the unique porous structure of Fe2O3,(ii)the superior visible light absorption of Fe2O3 nanoparticles,and(iii)the“bridge molecule”role of SDS efficiently improving the separation and transfer across the interfacial domain of SDS/Fe2O3 of photogenerated electron-hole pairs.More significantly,after the catalytic reaction,the SDS/Fe2O3 hybrids could be easily recovered using magnets and reused during subsequent cycles,which indicated their stability and recyclability. 展开更多
关键词 MIL-100(fe) fe2o3 SURFACTANT Photocatalytic denitrification PYRIDINE
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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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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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