TiO_2载体制备条件及结构对MnO_x/TiO_2催化剂性能的影响
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摘要
采用水热法一步反应制备锐钛矿结构TiO_2晶体,通过浸渍法负载活性组分MnO_x得到MnO_x/TiO_2低温脱硝催化剂。利用X射线衍射仪(XRD)、比表面积分析仪(BET)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)等手段,研究制备过程中水热温度、水热时间以及硫酸钠用量对TiO_2载体和MnO_x/TiO_2催化剂性能的影响。结果表明,水热温度为120℃,水热时间为22 h以及硫酸钠与尿素摩尔比为0.12的条件下,得到的TiO_2结晶度高,分散性好,最大比表面积为234.54 m~2·g~(-1)。由其制备的MnO_x/TiO_2低温脱硝催化剂具有最佳的低温脱硝活性,在空速为20000 h~(-1),反应温度为200℃时,催化剂脱硝率可达90%以上。
Anatase TiO_2 crystals were synthesized by one-pot hydrothermal reaction,and were used as carriers to prepare low-temperature denitrification catalysts MnO_x/TiO_2 by impregnation method. The effects of hydrothermal temperature,hydrothermal time and dosage of sodium sulfate on the performances of TiO_2 carriers and MnO_x/TiO_2 catalysts were investigated by XRD,BET,SEM and TEM. The results show that when the hydrothermal temperature is 120 ℃,the hydrothermal time is 22 h and the molar ratio of sodium sulfate to urea is 0. 12,the obtained TiO_2 carriers have high crystallinity,excellent dispersion properties and maximum specific surface area which is up to 234. 54 m~2·g~(-1). Moreover,under this conditions,the MnO_x/TiO_2 catalyst has the best low-temperature catalytic activity,when the reaction temperature is 200 ℃ and the space velocity is 20000 h~(-1),the NO conversion can up to 90%.
Anatase TiO_2 crystals were synthesized by one-pot hydrothermal reaction,and were used as carriers to prepare low-temperature denitrification catalysts MnO_x/TiO_2 by impregnation method. The effects of hydrothermal temperature,hydrothermal time and dosage of sodium sulfate on the performances of TiO_2 carriers and MnO_x/TiO_2 catalysts were investigated by XRD,BET,SEM and TEM. The results show that when the hydrothermal temperature is 120 ℃,the hydrothermal time is 22 h and the molar ratio of sodium sulfate to urea is 0. 12,the obtained TiO_2 carriers have high crystallinity,excellent dispersion properties and maximum specific surface area which is up to 234. 54 m~2·g~(-1). Moreover,under this conditions,the MnO_x/TiO_2 catalyst has the best low-temperature catalytic activity,when the reaction temperature is 200 ℃ and the space velocity is 20000 h~(-1),the NO conversion can up to 90%.
引文
[1]Liu C,Shi J W,Gao C,et al.Manganese oxide-based catalysts for low-temperature selective catalytic reduction of NO with NH3:a review[J].Applied Catalysis A:General,2016,522:54-69.
[2]Gong P J,Xie J L,Fang D,et al.Effects of surface physicochemical properties on NH3-SCR activity of Mn O2catalysts with different crystal structures[J].Chinese Journal of Catalysis,2017,38(11):1925-1934.
[3]崔海峰,谢峻林,李凤祥,等.SCR烟气脱硝技术的研究与应用[J].硅酸盐通报,2016,35(3):805-809.
[4]Gao F,Tang X,Yi H,et al.A review on selective catalytic reduction of NOxby NH3over Mn-based catalysts at low temperatures:catalysts,mechanisms,kinetics and DFT calculations[J].Catalysts,2017,7(7):199-230.
[5]柏林洋,蔡照胜,许琦.负载型低温NH3选择性还原锰基脱硝催化剂研究进展[J].化学世界,2016,57(9):596-600.
[6]马腾坤,房晶瑞,孟刘邦,等.Ti O2载体在SCR脱硝催化剂中应用的研究进展[J].硅酸盐通报,2016,35(6):1733-1737.
[7]Smirniotis P G,Pena D A,Uphade B S.Low-temperature selective catalytic reduction(SCR)of NO with NH3by using Mn,Cr,and Cu oxides supported on hombikat Ti O2[J].Angewandte Chemie International Edition,2001,40(13):2479-2482.
[8]孙秀果,张建民,周炬,等.锐钛型纳米二氧化钛的制备、表征及其机理的研究[J].人工晶体学报,2005,34(5):944-947.
[9]杨立荣,刘志刚,张丽,等.单分散介孔Ti O2微球的溶胶-凝胶法制备及其光催化性能[J].硅酸盐学报,2016,44(1):75-80.
[10]于海云,金春姬,包南.水热法制备锐钛矿相Ti O2纳米晶[J].人工晶体学报,2006,35(3):565-568.
[11]Wang F M,Shi Z S,Geng F,et al.Morphology control of anatase Ti O2by surfactant-assisted hydrothermal method[J].Chinese Journal of Chemical Engineering,2007,15(5):754-759.
[12]杜剑桥,王兰武.用Ti Cl4制备纳米Ti O2的研究状况[J].钛工业进展,2005,22(2):17-20.
[13]方德,谢峻林,胡华.锰离子价态对锰基脱硝催化剂性能的影响[J].武汉理工大学学报,2013,35(4):37-40.
[14]Panagiotis G S,Pavani M S,Donovan A P,et al.Titania supported bimetallic transition metal oxides for low-temperature SCR of NO with NH3[J].Industrial&Engineering Chemistry Research,2006,45:6444-6449.
[15]周珺,郑玉婴.不同形貌N-Ti O2的水热合成及其光催化性能研究[J].功能材料,2015,46(7):7148-7152.
[16]雷闫盈,俞行.均匀沉淀法制备纳米二氧化钛工艺条件研究[J].无机盐工业,2001,33(2):3-5.
[17]魏绍东,殷道纯.以Ti Cl4为原料制备纳米Ti O2技术的研究进展——液相法[J].现代涂料与涂装,2006,9(5):43-46.
[18]张青红,高濂.四氯化钛水解法制备二氧化钛纳米晶的影响因素[J].无机材料学报,2000,15(6):992-998.
[19]Ettireddy P R,Ettireddy,Mamedoy S,et al.Surface characterization studies of Ti O2supported manganese oxide catalysts for low temperature SCR of NO with NH3[J].Applied Catalysis B:Environmental,2007,76(1-2):123-134.
[20]黄晖,宫华,罗宏杰.水热沉淀法制备Ti O2纳米粉体影响因素的研究[J].中国陶瓷,2002,38(2):11-14.
[21]林嵩,徐宏,古宏晨.纳米Ti O2表面电位特性的研究[C].中国纳微粉体制备与技术应用研讨会,2003:544-546.
[22]欧秀娟,杜海燕.纳米Ti O2粉体的分散性研究[J].硅酸盐通报,2006,25(2):74-77.
[23]李作骏.多相催化反应动力学基础[M].北京:北京大学出版社,1990.
[2]Gong P J,Xie J L,Fang D,et al.Effects of surface physicochemical properties on NH3-SCR activity of Mn O2catalysts with different crystal structures[J].Chinese Journal of Catalysis,2017,38(11):1925-1934.
[3]崔海峰,谢峻林,李凤祥,等.SCR烟气脱硝技术的研究与应用[J].硅酸盐通报,2016,35(3):805-809.
[4]Gao F,Tang X,Yi H,et al.A review on selective catalytic reduction of NOxby NH3over Mn-based catalysts at low temperatures:catalysts,mechanisms,kinetics and DFT calculations[J].Catalysts,2017,7(7):199-230.
[5]柏林洋,蔡照胜,许琦.负载型低温NH3选择性还原锰基脱硝催化剂研究进展[J].化学世界,2016,57(9):596-600.
[6]马腾坤,房晶瑞,孟刘邦,等.Ti O2载体在SCR脱硝催化剂中应用的研究进展[J].硅酸盐通报,2016,35(6):1733-1737.
[7]Smirniotis P G,Pena D A,Uphade B S.Low-temperature selective catalytic reduction(SCR)of NO with NH3by using Mn,Cr,and Cu oxides supported on hombikat Ti O2[J].Angewandte Chemie International Edition,2001,40(13):2479-2482.
[8]孙秀果,张建民,周炬,等.锐钛型纳米二氧化钛的制备、表征及其机理的研究[J].人工晶体学报,2005,34(5):944-947.
[9]杨立荣,刘志刚,张丽,等.单分散介孔Ti O2微球的溶胶-凝胶法制备及其光催化性能[J].硅酸盐学报,2016,44(1):75-80.
[10]于海云,金春姬,包南.水热法制备锐钛矿相Ti O2纳米晶[J].人工晶体学报,2006,35(3):565-568.
[11]Wang F M,Shi Z S,Geng F,et al.Morphology control of anatase Ti O2by surfactant-assisted hydrothermal method[J].Chinese Journal of Chemical Engineering,2007,15(5):754-759.
[12]杜剑桥,王兰武.用Ti Cl4制备纳米Ti O2的研究状况[J].钛工业进展,2005,22(2):17-20.
[13]方德,谢峻林,胡华.锰离子价态对锰基脱硝催化剂性能的影响[J].武汉理工大学学报,2013,35(4):37-40.
[14]Panagiotis G S,Pavani M S,Donovan A P,et al.Titania supported bimetallic transition metal oxides for low-temperature SCR of NO with NH3[J].Industrial&Engineering Chemistry Research,2006,45:6444-6449.
[15]周珺,郑玉婴.不同形貌N-Ti O2的水热合成及其光催化性能研究[J].功能材料,2015,46(7):7148-7152.
[16]雷闫盈,俞行.均匀沉淀法制备纳米二氧化钛工艺条件研究[J].无机盐工业,2001,33(2):3-5.
[17]魏绍东,殷道纯.以Ti Cl4为原料制备纳米Ti O2技术的研究进展——液相法[J].现代涂料与涂装,2006,9(5):43-46.
[18]张青红,高濂.四氯化钛水解法制备二氧化钛纳米晶的影响因素[J].无机材料学报,2000,15(6):992-998.
[19]Ettireddy P R,Ettireddy,Mamedoy S,et al.Surface characterization studies of Ti O2supported manganese oxide catalysts for low temperature SCR of NO with NH3[J].Applied Catalysis B:Environmental,2007,76(1-2):123-134.
[20]黄晖,宫华,罗宏杰.水热沉淀法制备Ti O2纳米粉体影响因素的研究[J].中国陶瓷,2002,38(2):11-14.
[21]林嵩,徐宏,古宏晨.纳米Ti O2表面电位特性的研究[C].中国纳微粉体制备与技术应用研讨会,2003:544-546.
[22]欧秀娟,杜海燕.纳米Ti O2粉体的分散性研究[J].硅酸盐通报,2006,25(2):74-77.
[23]李作骏.多相催化反应动力学基础[M].北京:北京大学出版社,1990.
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