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基于V2O5/TiO2-Al2O3催化剂的甲醇选择性氧化制备二甲氧基甲烷 认领 引用 被引量:4
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作者 王拓 孟亚利 +1 位作者 曾亮 巩金龙 《科学通报》 CAS CSCD 北大核心 2015年第33期3272-3272,共1页
二甲氧基甲烷(DMM)是一种重要的有机合成中间体,也是香水和制药工业中的一种优良溶剂.此外,它也可被用作清洁的燃料或合成聚甲氧基二甲醚的起始单体.传统的DMM合成包括2个步骤:首先是甲醇部分氧化生成甲醛,其次是甲醇与甲醛在... 二甲氧基甲烷(DMM)是一种重要的有机合成中间体,也是香水和制药工业中的一种优良溶剂.此外,它也可被用作清洁的燃料或合成聚甲氧基二甲醚的起始单体.传统的DMM合成包括2个步骤:首先是甲醇部分氧化生成甲醛,其次是甲醇与甲醛在酸性催化剂作用下发生醇醛缩合生成DMM.然而,此方法有着诸多的局限性,如反应温度过高、工艺复杂、设备腐蚀严重等.另外,此反应还会生成甲酸甲酯、二甲醚、碳氧化物等副产物,降低DMM的选择性. 展开更多
关键词 二甲氧基甲烷 TiO2-Al2O3 酸性催化剂 选择性氧化 甲醇 V2O5 有机合成中间体 制备
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K2O对V2O5-WO3/TiO2催化剂的中毒作用 认领 引用 被引量:33
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作者 朱崇兵 金保升 +3 位作者 仲兆平 李锋 陈玲霞 翟俊霞 《东南大学学报(自然科学版)》 EI CAS 北大核心 2008年第1期101-105,共5页
实验室制备了V2O5-WO3/TiO2的脱硝催化剂,采用模拟中毒法,在此催化剂上负载碱金属氧化物K2O,通过BET,XRD,SEM等方法对微观结构进行表征.在SCR活性试验台上研究不同含量K2O对催化剂脱硝活性,N2O生成率和SO2氧化率的影响.结果发现:K2O对... 实验室制备了V2O5-WO3/TiO2的脱硝催化剂,采用模拟中毒法,在此催化剂上负载碱金属氧化物K2O,通过BET,XRD,SEM等方法对微观结构进行表征.在SCR活性试验台上研究不同含量K2O对催化剂脱硝活性,N2O生成率和SO2氧化率的影响.结果发现:K2O对于催化剂的毒性较强,随着添加量的增大,NO脱除率急剧下降,SO2的氧化率大大提高;较大含量的K2O(nKV=1,摩尔比)使催化剂比表面积有所减少,催化剂颗粒发生轻微团聚,微观结构变化不大,但NO的脱除率小于50%(380℃),N2O的生成率和SO2的氧化率均增加;K2O通过与V2O5的活性酸性位结合,使催化剂中有效活性位数量大为降低,导致脱硝活性下降. 展开更多
关键词 中毒 K2O V2O5-WO3/TiO2催化剂 SCR 脱硝
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商业V_2O_5-WO_3/TiO_2催化剂SCR脱硝过程中PM2.5的排放特性及影响因素研究 认领 引用 被引量:31
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作者 张玉华 束航 +2 位作者 范红梅 张亚平 杨林军 《中国电机工程学报》 EI CSCD 北大核心 2015年第2期383-389,共7页
针对V2O5-WO3/Ti O2商用催化剂,采用电称低压冲击器(ELPI)、PM10/PM2.5采样器、X-射线衍射(XRD)、场发射扫描电镜-能谱分析(FSEM-EDX)等对SCR烟气脱硝中形成的细颗粒粒径分布、形貌、元素及物相组成进行了测试分析,并研究了烟气组分及... 针对V2O5-WO3/Ti O2商用催化剂,采用电称低压冲击器(ELPI)、PM10/PM2.5采样器、X-射线衍射(XRD)、场发射扫描电镜-能谱分析(FSEM-EDX)等对SCR烟气脱硝中形成的细颗粒粒径分布、形貌、元素及物相组成进行了测试分析,并研究了烟气组分及反应条件对SCR脱硝系统出口细颗粒物性的影响。结果表明,SCR脱硝过程中会形成不少亚微米级颗粒,主要成分为硫酸铵以及硫酸氢氨,晶型呈块状。细颗粒生成量随反应温度的升高和NH3/NO摩尔比的增加而增加,在脱硝效率较高时,颗粒物形成量也趋于增多;烟气中SO2、H2O和O2浓度的增加均会导致细颗粒物形成量的增加。导致细颗粒物产生的主要原因可归结于催化剂的活性组分对SO2的氧化以及SCR脱硝反应中NH3的逃逸。 展开更多
关键词 选择性催化还原(SCR) PM2.5 形成 排放特性 影响因素 V2O5-WO3/TiO2
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Effects of silica additive on the NH_3-SCR activity and thermal stability of a V_2O_5/WO_3-TiO_2 catalyst 认领 引用 被引量:24
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作者 刘雪松 吴晓东 +3 位作者 许腾飞 翁端 司知蠢 冉锐 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1340-1346,共7页
V2O5/WO3‐TiO2 and V2O5/WO3‐TiO2‐SiO2 catalysts were prepared by a wetness impregnation method, and both the catalysts were hydrothermally aged at 750℃ in 10 vol%H2O/air for 24 h. The catalysts were evaluated for N... V2O5/WO3‐TiO2 and V2O5/WO3‐TiO2‐SiO2 catalysts were prepared by a wetness impregnation method, and both the catalysts were hydrothermally aged at 750℃ in 10 vol%H2O/air for 24 h. The catalysts were evaluated for NOx conversion using NH3 as the reductant. Hydrothermal ageing decreased the NOx conversion of V2O5/WO3‐TiO2 catalyst severely over the entire measured tem‐perature range. Interestingly, the NH3‐SCR activity of the silica‐modified catalyst at 220–480℃ is enhanced after ageing. The catalysts were characterized by X‐ray diffraction, nitrogen adsorption, X‐ray fluorescence, Raman spectroscopy, H2 temperature‐programmed reduction, and NH3 temper‐ature‐programmed desorption. The addition of silica inhibited the phase transition from anatase to rutile titania, growth of TiO2 crystallite size and shrinkage of catalyst surface area. Consequently, the vanadia species remained highly dispersed and the hydrothermal stability of the V2O5/WO3‐TiO2 catalyst was significantly improved. 展开更多
关键词 V2O5/WO3-TiO2 Silica NH3-SCR Hydrothermal stability Polymeric vanadia De-NOx
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V2O5-WO3/TiO2烟气脱硝催化剂的载体选择 认领 引用 被引量:50
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作者 朱崇兵 金保升 +2 位作者 仲兆平 李锋 翟俊霞 《中国电机工程学报》 EI 北大核心 2008年第11期41-47,共7页
在选择性催化还原试验台上对4种不同TiO2为载体制备的催化剂的脱硝性能进行测试,采用BET、X射线衍射、傅里叶转换红外光谱、扫描电镜-能谱分析、X射线荧光分析和热重分析等技术进行微观表征,并与商业催化剂进行对比。以硫酸法制备的纳... 在选择性催化还原试验台上对4种不同TiO2为载体制备的催化剂的脱硝性能进行测试,采用BET、X射线衍射、傅里叶转换红外光谱、扫描电镜-能谱分析、X射线荧光分析和热重分析等技术进行微观表征,并与商业催化剂进行对比。以硫酸法制备的纳米级锐钛型TiO2适合作为选择性催化还原催化剂载体,制备的催化剂脱硝效率高,温度窗口宽,选择性好,其中硫酸盐质量分数为8%~10%时最为有利;以氯化法制备纳米TiO2过程中,生成了V3Ti6O17的聚合物导致NO脱除率较低,因此不适合作为催化剂载体。以工业级TiO2为载体制备的催化剂氨氮比为1.0时,在355~420℃的温度范围内NO脱除率为80%~85%,但由于成本很低,因此可以用于脱硝要求不高的场合。由钛酸丁酯溶胶法制备TiO2为载体制备的SCR催化剂性能不及硫酸法制备的纳米级锐钛型TiO2制备的催化剂,且操作复杂,技术难度大,不适宜推广。 展开更多
关键词 V2O5-WO3/TiO2 催化剂载体 选择性催化还原 烟气脱硝 纳米级锐钛型TiO2
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Pr掺杂对V2O5-MoO3/TiO2催化剂NH3-SCR反应活性的影响 认领 引用 被引量:33
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作者 晁晶迪 何洪 +5 位作者 宋丽云 房玉娇 梁全明 张桂臻 邱文革 张然 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2015年第3期523-530,共8页
采用溶胶一凝胶法制备了不同Pr掺杂量的Pr6O11-TiO2载体,并以浸渍法制备了V2O5-MoO3/Pr6O11-TiO2催化剂.活性评价结果表明,该催化剂在220~400℃范围内具有良好的脱硝效率和N2选择性以及较强的抗SO2和H2O性能.表征结果表明,掺杂P... 采用溶胶一凝胶法制备了不同Pr掺杂量的Pr6O11-TiO2载体,并以浸渍法制备了V2O5-MoO3/Pr6O11-TiO2催化剂.活性评价结果表明,该催化剂在220~400℃范围内具有良好的脱硝效率和N2选择性以及较强的抗SO2和H2O性能.表征结果表明,掺杂Pr可以提高V2O5-MoO3/TiO2催化剂的比表面积、表面化学吸附氧物种浓度、桥式硝酸盐物种和Brionsted酸位数量,从而提高了催化剂上NHx的选择性催化还原(NH3-SCR)活性。 展开更多
关键词 Pr掺杂 V2O5-MoO3/TiO2催化剂 选择性催化还原 氨气
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Effect of Ce doping into V2O5-WO3/TiO2 catalysts on the selective catalytic reduction of NOx by NH3 认领 引用 被引量:27
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作者 Mengyin Chen Mengmeng Zhao +3 位作者 Fushun Tang Le Ruan Hongbin Yang Ning Li 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第12期1206-1215,共10页
In this work, the effectiveness of V2O5-WO3/TiO2 catalysts modified with different CeO2 contents by impregnation and co-precipitation methods on the selective catalytic reduction of NOxby NH3 have been studied compara... In this work, the effectiveness of V2O5-WO3/TiO2 catalysts modified with different CeO2 contents by impregnation and co-precipitation methods on the selective catalytic reduction of NOxby NH3 have been studied comparatively by various experimental techniques. The results showed that the NO conversion of V2O5-WO3/CeO2-TiO2 catalysts modified by co-precipitation method obviously increased with the Ce doping contents in the studied range below 20%(All Ce contents are in mass fractions), but the NO conversion of V2O5-WO3/CeO2/TiO2 catalysts modified by impregnation methods was lower than V2O5-WO3/CeO2-TiO2 catalysts especially beyond 2.5% Ce doping contents. The V2O5-WO3/CeO2-TiO2 catalysts showed better SCR activity, wider reaction window, and higher sulfur and water resistance. The characterization results elucidated that the modified catalysts by co-precipitation method exhibited higher specific surface area, much better dispersity of Ce component, more Ce^(3+)species and more Br?nsted acid sites than that by impregnation. The vacancies caused by more Ce^(3+)species were favorable for more NO oxidation to NO2, and the interaction between Ce species and WOxspecies generated more Br?nsted acid sites. It could be supposed that dispersed Ce Oxspecies and WOxspecies offered more second active centers respectively to adsorb oxygen and activate ammonia as co-catalysis to the primary active center of V ions, thus facilitated the better SCR activity of modified V2O5-WO3/CeO2-TiO2 catalysts by coprecipitation methods. The co-precipitation methods with Ce component were more suitable for production of modified commercial V2O5-WO3/TiO2 catalysts. 展开更多
关键词 V2O5-WO3/TiO2 catalysts Ce doping methods NH3 selective catalytic reduction NOx Dispersion state Reducibility Br?nsted acid sites
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Improving the denitration performance and K-poisoning resistance of the V_2O_5-WO_3/TiO_2 catalyst by Ce4+ and Zr4+ co-doping 认领 引用 被引量:21
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作者 Jun Cao Xiaojiang Yao +4 位作者 Fumo Yang Li Chen Min Fu Changjin Tang Lin Dong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第1期95-104,共10页
A series of V2O5‐WO3/TiO2‐ZrO2,V2O5‐WO3/TiO2‐CeO2,and V2O5‐WO3/TiO2‐CeO2‐ZrO2 catalysts were synthesized to improve the selective catalytic reduction(SCR)performance and the K‐poisoning resistance of a V2O5‐W... A series of V2O5‐WO3/TiO2‐ZrO2,V2O5‐WO3/TiO2‐CeO2,and V2O5‐WO3/TiO2‐CeO2‐ZrO2 catalysts were synthesized to improve the selective catalytic reduction(SCR)performance and the K‐poisoning resistance of a V2O5‐WO3/TiO2 catalyst.The physicochemical properties were investigated by using XRD,BET,NH3‐TPD,H2‐TPR,and XPS,and the catalytic performance and K‐poisoning resistance were evaluated via a NH3‐SCR model reaction.Ce^4+and Zr^4+co‐doping were found to enhance the conversion of NOx,and exhibit the best K‐poisoning resistance owing to the largest BET‐specific surface area,pore volume,and total acid site concentration,as well as the minimal effects on the surface acidity and redox ability from K poisoning.The V2O5‐WO3/TiO2‐CeO2‐ZrO2 catalyst also presents outstanding H2O+SO2 tolerance.Finally,the in situ DRIFTS reveals that the NH3‐SCR reaction over the V2O5‐WO3/TiO2‐CeO2‐ZrO2 catalyst follows an L‐H mechanism,and that K poisoning does not change the reaction mechanism. 展开更多
关键词 V2O5‐WO3/TiO2‐CeO2‐ZrO2 catalyst Co‐doping K‐poisoning NH3‐SCR Reaction mechanism
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蜂窝状V_2O_5-WO_3/TiO_2催化剂脱硝性能研究 认领 引用 被引量:46
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作者 朱崇兵 金保升 +3 位作者 李锋 仲兆平 翟俊霞 陈玲霞 《中国电机工程学报》 EI 北大核心 2007年第29期45-50,共6页
实验室制备了蜂窝状V2O5-WO3/TiO2的脱硝催化剂,通过BET、XRD、SEM等方法对微观结构进行表征。在自制SCR活性试验台上测试各种运行工况(温度、空速比等)和烟气组成([NH3]/[NO]、水蒸气等)对催化剂的脱硝活性、选择性、SO,的氧... 实验室制备了蜂窝状V2O5-WO3/TiO2的脱硝催化剂,通过BET、XRD、SEM等方法对微观结构进行表征。在自制SCR活性试验台上测试各种运行工况(温度、空速比等)和烟气组成([NH3]/[NO]、水蒸气等)对催化剂的脱硝活性、选择性、SO,的氧化率和氨逃逸量的影响。研究结果表明,自制蜂窝状催化剂在空速比小于3500h^-1、NH3/NO在0.9-1.0、温度320-420℃范围内的NO脱除率较高、SO2氧化率和氨逃逸量较低,基本达到工业应用的要求;低含量(低于2%)水蒸气可以提高高温段NO脱除率,而高含量的水蒸气对催化剂NO脱除具有明显的抑制作用,但水蒸气的加入会使NO脱除温度范围拓宽;由于催化剂自身含有较多的硫酸盐,未观察到SO2对脱硝反应有促进作用。 展开更多
关键词 蜂窝状 V2O5-WO3/TiO2催化剂 选择性催化还原 脱硝
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钾盐对V_2O_5/TiO_2催化剂NH_3选择性催化还原NO反应的影响 认领 引用 被引量:29
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作者 姜烨 高翔 +3 位作者 杜学森 毛剑宏 骆仲泱 岑可法 《中国电机工程学报》 EI 北大核心 2008年第35期21-26,共6页
钾在中国燃煤和生物质烟气中以钾盐——硫酸钾和氯化钾的形式存在。文中采用静态N2物理吸附、程序升温表面反应(temperature-programmed surface reaction,TPSR)、傅里叶变换红外(Fourier transform infrared,FT-IR)光谱和催化活性评价... 钾在中国燃煤和生物质烟气中以钾盐——硫酸钾和氯化钾的形式存在。文中采用静态N2物理吸附、程序升温表面反应(temperature-programmed surface reaction,TPSR)、傅里叶变换红外(Fourier transform infrared,FT-IR)光谱和催化活性评价的方法,研究了钾盐对V2O5/TiO2催化剂上NH3选择性催化还原NO反应的影响。结果表明,钾盐使V2O5/TiO2催化剂活性降低。随着钾盐在催化剂上负载量的增加,稳定的NO脱除温度窗口逐渐变窄,当K与V物质的量之比达到3.0时,该窗口消失。钾盐的掺入使催化剂表面活性位数量明显减少,但是并没有显著改变催化剂的反应性。催化剂失活的主要原因是K优先配位在催化剂表面的Br¢nsted酸性位上,中和了Br¢nsted酸性位酸性,使Br¢nsted酸性位上吸附的氨减少。 展开更多
关键词 选择性催化还原 氮氧化物 钾盐 V2O5/TiO2催化剂 活性
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纳米负载型V_2O_5-WO_3/TiO_2催化剂碱中毒及再生研究 认领 引用 被引量:51
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作者 沈伯雄 熊丽仙 +2 位作者 刘亭 王静 田晓娟 《燃料化学学报》 北大核心 2010年第1期85-90,共6页
实验制备了陶瓷颗粒为骨架的纳米级V2O5-WO3/TiO2(C)催化剂。采用浸渍法模拟碱金属中毒,研究了中毒及再生对催化剂脱硝活性的影响,运用XRD、FT-IR、H2-TPR、XPS技术表征分析了碱金属对催化剂的失活作用。实验表明,碱金属能使催化剂活性... 实验制备了陶瓷颗粒为骨架的纳米级V2O5-WO3/TiO2(C)催化剂。采用浸渍法模拟碱金属中毒,研究了中毒及再生对催化剂脱硝活性的影响,运用XRD、FT-IR、H2-TPR、XPS技术表征分析了碱金属对催化剂的失活作用。实验表明,碱金属能使催化剂活性降低,钾的毒性大于钠。FT-IR结果显示,催化剂以Lewis酸作为活性酸位。H2-TPR、XPS结果表明,钾的加入降低了催化剂的氧化能力,主要影响了催化剂表面的吸附氧。采用单纯的水洗方法并不能提高催化剂活性,而酸洗再生后催化剂在较高反应温度下活性得到较好的恢复。 展开更多
关键词 选择性催化还原 V2O5-WO3/TiO2 脱硝 碱金属 催化剂中毒 再生
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前驱体溶液pH值对V_2O_5-WO_3/TiO_2催化剂的低温NH_3-SCR性能的影响(英文) 认领 引用 被引量:26
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作者 董国君 张玉凤 +1 位作者 赵元 白洋 《燃料化学学报》 CSCD 北大核心 2014年第12期1455-1463,共9页
采用调节前驱体溶液pH值的方法制备了用于低温NH3-SCR的V2O5-WO3/Ti O2催化剂。通过XPS、Raman光谱、H2-TPR、NH3-TPD、NH3-DRIFT、XRD及物理吸附等手段对催化剂进行了表征分析,并对其脱硝催化活性进行了测试。结果表明,前驱体溶液酸性... 采用调节前驱体溶液pH值的方法制备了用于低温NH3-SCR的V2O5-WO3/Ti O2催化剂。通过XPS、Raman光谱、H2-TPR、NH3-TPD、NH3-DRIFT、XRD及物理吸附等手段对催化剂进行了表征分析,并对其脱硝催化活性进行了测试。结果表明,前驱体溶液酸性的增强能够提高催化剂表面聚合态钒物种和V4+(3+)/V5+的比值以及表面酸性,增加活性位数量、降低反应的活化能、提高其脱硝催化性能。因此,通过提高前驱体溶液的酸性,有助于制备出脱硝活性较好的NH3-SCR催化剂。 展开更多
关键词 前驱体溶液 V2 O5-WO3/TiO2 pH值 低温NH3-SCR 钒物种 脱硝活性
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Promotional effect of Si-doped V_2O_5/TiO_2 for selective catalytic reduction of NOx by NH_3 认领 引用 被引量:17
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作者 Yanxiao Pan Wei Zhao +2 位作者 Qin Zhong Wei Cai Hongyu Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第8期1703-1711,共9页
TiO2 supports doped with different amounts of Si were prepared by a sol-gel method, and 1 wt% vanadia (V2O5) loaded on Si-doped TiO2 was obtained by an impregnation method. The mole ratio of Si/Ti was 0.2, NOx conve... TiO2 supports doped with different amounts of Si were prepared by a sol-gel method, and 1 wt% vanadia (V2O5) loaded on Si-doped TiO2 was obtained by an impregnation method. The mole ratio of Si/Ti was 0.2, NOx conversion exceeds 94% at 300℃ and GHSV of 41,324 hr-1 , which is about 20% higher than pure V2O5/TiO2 . The catalysts were characterized by XRD, BET, TEM, FT-IR, NH3-TPD, XPS, H2-TPR, Raman and in situ DRIFTS. The results of FT-IR and XPS indicated that Si was doped into the TiO2 lattice successfully and a solid solution was obtained. V2O5 active component could be dispersed well on the support with the increasing of surface area of the catalyst, which was confirmed by Raman and XRD results. Above all, the numbers of acid sites (especially the Br nsted-acid) and oxidation properties were enhanced for Si-doped V2O5/TiO2 catalysts, which improved the deNOx catalytic activity. 展开更多
关键词 Si-doped V2O5/TiO2 SCR Si-O-Ti VOx species
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Performance of V_2O_5-WO_3-MoO_3/TiO_2 Catalyst for Selective Catalytic Reduction of NO_x by NH_3 认领 引用 被引量:17
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作者 高岩 栾涛 +2 位作者 吕涛 程凯 徐宏明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第1期1-7,共7页
The V/O5-WO3-MoOy'TiO2 honeycomb catalyst was prepared with industrial grade chemicals. The structural and physico-chemical properties were analyzed with X-ray diffraction (XRD), scanning electron micrograph (SEM... The V/O5-WO3-MoOy'TiO2 honeycomb catalyst was prepared with industrial grade chemicals. The structural and physico-chemical properties were analyzed with X-ray diffraction (XRD), scanning electron micrograph (SEM) and mercury porosimetry. The NOx conversion and durability were investigated on a pilot plant test set under the actual operational conditions of a coal fired boiler. The catalyst monolith had good formability with mass per- centage of V : W : Mo : TiO2 : fiber glass = 1 : 4.5 : 4.5 : 72 : 18. Vanadium, tungsten and molybdenum species were highly dispersed on anatase TiO2 without causing the transformation of anatase TiO2 to ruffle by calcining under a current of air at 450℃ for 4.5 h, but there were some degrees of crystal distortion. The catalyst particle sizes were almost uniform with close pile-up and the pore structure was regular with complete macro-pore formation and large specific surface area. The NOx conversion was sensitive to temperature but nearly insensitive to NH3. The catalyst showed strong adaptability to NOx concentration with activity above 80% in the range of 615 1640 mg.m-3. Within the range of 720-8640 h continuous operation, the NOx conversion dropped at a rate of about 1% reduction per 600 h. 展开更多
关键词 selective catalytic reduction V2O5-WO3-MoO3/ZiO2 catalyst physico-chemical property flue gas life time
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Y改性对V2O5-MoO3/TiO2催化剂脱硝性能的影响 认领 引用 被引量:15
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作者 黄力 王虎 +3 位作者 纵宇浩 常峥峰 于洋 张鑫 《现代化工》 CAS CSCD 北大核心 2020年第3期162-166,共5页
为提升V2O5-MoO3/TiO2催化剂的脱硝性能,扩展催化剂活性温度窗口,对催化剂进行Y改性处理。采用XRD、N2-吸附脱附、H2-TPR、拉曼光谱、NH3-TPD、XPS等手段对催化剂进行表征。结果表明,添加0.3%的Y可以增加催化剂上聚合钒物种,提高催化剂V... 为提升V2O5-MoO3/TiO2催化剂的脱硝性能,扩展催化剂活性温度窗口,对催化剂进行Y改性处理。采用XRD、N2-吸附脱附、H2-TPR、拉曼光谱、NH3-TPD、XPS等手段对催化剂进行表征。结果表明,添加0.3%的Y可以增加催化剂上聚合钒物种,提高催化剂V4+/V5+、(V4++V3+)/V5+的摩尔比率,同时,还能增加催化剂上化学吸附氧(Oα)的含量。然而,过量的(0.6%、0.9%)Y会导致催化剂还原性能和酸性性能的显著降低,对催化剂的脱硝性能有负面影响。4种催化剂中,VMo Y(0.3)/Ti催化剂的脱硝活性最佳。 展开更多
关键词 SCR 脱硝催化剂 V2O5-MoO3/TiO2
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Thermal stability of Si-doped V2O5/WO3-TiO2 for selective catalytic reduction of NOx by NH3 认领 引用 被引量:15
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作者 Xun-Zhe Shao Hong-You Wang +5 位作者 Meng-Long Yuan Jie Yang Wang-Cheng Zhan Li Wang Yun Guo Guan-Zhong Lu 《Rare Metals》 SCIE EI CAS CSCD 2019年第4期292-298,共7页
The selective catalytic reduction of NOV with NH3 (NH3-SCR) is a very effective technology to control the emission of NOA, and the thermal stability of NH3-SCR catalyst is very important for removal of NOV from diesel... The selective catalytic reduction of NOV with NH3 (NH3-SCR) is a very effective technology to control the emission of NOA, and the thermal stability of NH3-SCR catalyst is very important for removal of NOV from diesel engines. In this work, V2O5/WO3-TiO2 (VWT) and SiO2- doped V2O5/WO3-TiO2 (VWTSi10)) catalysts were prepared by impregnation method and characterized by Brunauer- Emmett-Teller (BET), X-ray diffraction (XRD), Raman, temperature programmed reduction by hydrogen (H2-TPR), X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption by ammonia (NH3- TPD). The doping of SiO2 promotes the thermal stability of V2O5/WO3-TiO? for NH3-SCR significantly. After calcination at 650 °C for 50 h, the operation window of 10% SiO2-doped V2O5/WO3-TiO2 is 220-480 °C, while the maximum NOV conversion on V2O5/WO3-TiO2 is about 77%. The presenee of SiO2 obviously blocks the transformation of TiO2 from anatase to rutile and stabilizes the dispersion of VOv and WO3 on the surface. It is available for the existence of V44 and the amount of surface acid sites increases, which inhabits the NH3 oxidation at the high temperature range and promotes NH3-SCR activity. 展开更多
关键词 V2O5/WO3-TiO2 SiO2 NH3-SCR Thermal stability
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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 认领 引用 被引量:12
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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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Fe_2O_3对V_2O_5-WO_3/TiO_2催化剂表面性质及其性能的影响 认领 引用 被引量:14
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作者 刘建华 杨晓博 +3 位作者 张琛 吴凡 李忠 夏启斌 《化工学报》 EI CSCD 北大核心 2016年第4期1287-1293,共7页
催化剂是选择性催化还原(SCR)脱硝技术的核心,研究Fe对钒钛系SCR催化剂脱硝活性及SO_2/SO_3转化率的影响具有重要意义。采用等体积浸渍法制备了不同Fe/V质量比的Fe_2O_3-V2O_5-WO_3/TiO_2催化剂,并进行表征,研究Fe对钒钛系SCR催化剂脱... 催化剂是选择性催化还原(SCR)脱硝技术的核心,研究Fe对钒钛系SCR催化剂脱硝活性及SO_2/SO_3转化率的影响具有重要意义。采用等体积浸渍法制备了不同Fe/V质量比的Fe_2O_3-V2O_5-WO_3/TiO_2催化剂,并进行表征,研究Fe对钒钛系SCR催化剂脱硝活性及SO_2/SO_3转化率的影响,并讨论Fe对于钒钛系SCR催化剂表面性质的影响。结果表明,随着催化剂表面Fe_2O_3含量增加,催化剂的脱硝效率及二氧化硫氧化率均是先上升后下降,当Fe/V质量比为3.0时,催化剂的脱硝效率和二氧化硫氧化率均达到最大值91.78%、1.01%。XPS及H_2-TPR结果表明,随着Fe_2O_3含量增加,催化剂表面钒活性组分的相对含量及V4+/V5+比减小,催化剂表面吸附氧(Oα)浓度增加,催化剂的氧化能力增强。NO-TPD结果表明,随着Fe_2O_3含量增加,催化剂表面吸附NO的能力增强。 展开更多
关键词 V2O5-WO3/TiO2 选择性催化还原 催化剂 载体
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燃煤烟气中砷对V_2O_5-WO_3/TiO_2 SCR脱硝催化剂性能的影响 认领 引用 被引量:16
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作者 丁健 刘清才 +3 位作者 孔明 林凡 杨剑 任山 《燃料化学学报》 CSCD 北大核心 2016年第4期495-499,共5页
通过将商业V_2O_5-WO_3/TiO_2脱硝催化剂暴露于含As_2O_3烟气中,制备了砷中毒催化剂,并运用X射线衍射(XRD)、比表面积(BET)、NH3化学吸附、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱等技术表征分析了砷对催化剂性能的影响,并提出了... 通过将商业V_2O_5-WO_3/TiO_2脱硝催化剂暴露于含As_2O_3烟气中,制备了砷中毒催化剂,并运用X射线衍射(XRD)、比表面积(BET)、NH3化学吸附、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱等技术表征分析了砷对催化剂性能的影响,并提出了催化剂砷中毒机理。结果表明,砷对催化剂具有严重的毒害作用,As_2O_3会吸附在催化剂表面,并被催化剂氧化形成As_2O_5覆盖层,减小催化剂比表面积,减少催化剂V活性位,阻止催化剂对NH3的吸附,造成催化剂失活。 展开更多
关键词 砷中毒 V2O5-WO3/TiO2催化剂 As2O3 失活
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Effects of different introduction methods of Ce^4+and Zr^4+on denitration performance and anti-K poisoning performance of V2O5-WO3/TiO2 catalyst 认领 引用 被引量:11
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作者 Jun Cao Xiaojiang Yao +3 位作者 Li Chen Keke Kang Min Fu Yang Chen 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第11期1207-1214,I0003,共8页
The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reducti... The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by NH3.Four different methods,namely pre-impregnation,post-impregnation,coimpregnation,and co-precipitation,were used to synthesize a series of V2 O5-WO3-TiO2-CeO2-ZrO2 catalysts.The catalysts were characterized by XRD,BET,NH3-TPD,XPS,and H2-TPR techniques.Moreover,the activity and anti-K poisoning performance were tested by an NH3-SCR model reaction.The results show that the introduction of Ce^4+and Zr^4+can improve the catalytic performance of V2O5-WO3/TiO2 catalyst,but the impregnation method cannot enhance the anti-K poisoning performance.Ce^4+and Zr^4+introduced by co-precipitation method can effectively improve the tolerance of K,which is mainly due to the incorporation of Ce^4+and Zr^4+into TiO2 lattice to form a uniform TiO2-CeO2-ZrO2 solid solution,resulting in the optimal surface acidity and redox performance,and reducing the decreases caused by Kpoisoning.Furthermore,based on the best introduction method,we further optimized the molar ratio of Ce^4+/Zr^4+,It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce^4+/Zr^4+is 2:1. 展开更多
关键词 V2O5-WO3/TiO2 denitration catalyst Ce^4+,Zr^4+modification Introduction methods Molar ratio Anti-K poisoning performance Rare Earths
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