铌元素改性V2O5-WO3/TiO2催化剂降低脱硝过程 SO2 的氧化率

王博; 边瑶; 封硕; 王少奇; 沈伯雄

doi:10.1016/S1872-5813(21)60177-9

铌元素改性V₂O₅-WO₃/TiO₂催化剂降低脱硝过程 SO₂ 的氧化率

doi: 10.1016/S1872-5813(21)60177-9

王博^1,,
边瑶¹,
封硕¹,
王少奇¹,
沈伯雄^{1, 2, ,}

1.
河北工业大学能源与环境工程学院, 天津市清洁能源利用与污染物控制重点实验室, 天津 300401
2.
河北工业大学化工学院, 天津 300401

基金项目: 国家自然科学基金(U20A20302), 天津市重点研发项目(19ZXZSN00050,19ZXSZSN00070), 河北省重点研发项目(20373701D)和河北省重大科技攻关项目(21283701Z)资助

详细信息

通讯作者:
E-mail: shenbx@hebut.edu.cn

中图分类号: X51;TQ42
计量
- 文章访问数: 431
- HTML全文浏览量: 120
- PDF下载量: 27
- 被引次数: 0
出版历程
- 收稿日期: 2021-09-16
- 修回日期: 2021-10-20
- 录用日期: 2021-10-20
- 网络出版日期: 2021-11-15
- 刊出日期: 2022-04-26

Modification of the V₂O₅-WO₃/TiO₂ catalyst with Nb to reduce its activity for SO₂ oxidation during the selective catalytic reduction of NO_x

WANG Bo^1
,,
BIAN Yao¹,
FENG Shuo¹,
WANG Shao-qi¹,
SHEN Bo-xiong^{1, 2
, ,}

1.
College of Energy and Environmental Engineering, Hebei University of Technology, Key Laboratory of Clean Energy Utilization and Pollutant Control in Tianjin, Tianjin 300401, China
2.
College of chemical engineering, Hebei University of Technology, Tianjin 300401, China

Funds: The project was supported by Joint Funds of the National Natural Science Foundation of China (U20A20302), Key R & D Projects in Tianjin (19ZXSZSN00050, 19ZXSZSN00070), Key R & D projects in Hebei Province (20373701D), and Project of Great Transformation of Scientific and Technical Research in Hebei Province (21283701Z).

摘要

摘要: 本文采用浸渍法制备了Nb改性的V₂O₅-WO₃/TiO₂催化剂，研究了脱硝反应中Nb负载量对催化剂SO₂氧化活性的影响。结果表明，在350 °C下，Nb₂O₅负载量为2%的Nb₂O₅-V₂O₅-WO₃/TiO₂催化剂上的SO₂氧化率最低（0.6%），而同时NO_x 的转化率仍能达到95%。采用TGA、氮吸附、XRD、H₂-TPR、CO₂-TPD、XPS和in- situ DRIFTS等对催化剂进行了表征分析，结果显示，Nb改性后V₂O₅-WO₃/TiO₂催化剂的晶体结构没有发生明显改变，但是其比表面积小幅度下降，有助于减少对SO₂的吸附；同时，改性后催化剂表面的吸附氧含量下降，氧化还原性能也稍微减弱，这有利于降低其对SO₂的氧化活性。in-situ DRIFTS结果表明，Nb改性后的Nb-V₂O₅-WO₃/TiO₂催化剂反应过程中表面中间产物VOSO₄的含量明显下降，从而减少了SO₃的生成量。
- SO₂氧化 /
- Nb改性 /
- V₂O₅-WO₃/TiO₂催化剂 /
- NH₃-SCR脱硝
Abstract: A series of Nb-modified V₂O₅-WO₃/TiO₂ catalysts were prepared by the impregnation method and the effect of Nb loading on their SO₂ oxidation activity during the selective catalytic reduction of NO_x was investigated. The results indicate that the Nb₂O₅-V₂O₅-WO₃/TiO₂ catalyst with a Nb₂O₅ loading of 2% exhibits the lowest SO₂ conversion of 0.6% for oxidation at 350 °C, whereas the conversion of NO_x is still above 95%. The catalysts were characterized by TGA, BET, XRD, H₂-TPR, CO₂-TPD, XPS and in-situ DRIFTS. The results illustrate that the influence of Nb modification on the crystal structure of V₂O₅-WO₃/TiO₂ catalyst is rather insignificant; however, the surface area of the Nb₂O₅-V₂O₅-WO₃/TiO₂ catalyst decreases slightly after the modification with Nb, conducing to a decrease of SO₂ adsorption on the catalyst. Meanwhile, the content of oxygen adsorbed on the catalyst surface decreases considerably upon the Nb modification, suggesting a weakened redox performance, which is beneficial to reducing the oxidation of SO₂. The in-situ DRIFTS results illustrate that the content of the intermediate VOSO₄ product on the catalyst surface decreases over the Nb-modified Nb₂O₅-V₂O₅-WO₃/TiO₂ catalyst, leading to a decrease of SO₃ production.
- SO₂ oxidation /
- Nb modification /
- V₂O₅-WO₃/TiO₂ /
- removal of NO_x by NH₃-SCR

HTML全文

FIG. 1472. FIG. 1472.

下载: 全尺寸图片幻灯片

图 1 催化剂测试系统示意图

Figure 1 Catalyst testing system

1: gas; 2: pressure reducing valve; 3: mass flowmeter; 4: gas mixer; 5: imported flue gas sampler; 6:reactor; 7: temperature control instrument; 8: condenser tube; 9: peristaltic pump; 10: water bath; 11: gas treatment units

下载: 全尺寸图片幻灯片

图 2 不同Nb负载量催化剂对SO₂氧化率的影响

Figure 2 Effect of Nb loading on SO₂ conversion upon oxidation over the Nb-modified catalysts

下载: 全尺寸图片幻灯片

图 3 不同Nb负载量催化剂对NH₃-SCR活性的影响

Figure 3 Effect of Nb loading on the NO conversion in NH₃-SCR deNO_x over the Nb-modified catalysts

下载: 全尺寸图片幻灯片

图 4 催化剂脱硝和SO₂氧化效率

Figure 4 Catalytic performance of various catalysts in the simultaneous denitration and SO₂ oxidation

下载: 全尺寸图片幻灯片

图 5 催化剂的N₂吸附-脱附等温曲线

Figure 5 Nitrogen desorption and desorption isotherms of various catalysts

下载: 全尺寸图片幻灯片

图 6 催化剂的孔径分布

Figure 6 Pore size distribution curves of various catalysts

下载: 全尺寸图片幻灯片

图 7 催化剂的XRD谱图

Figure 7 XRD patterns of various catalysts

下载: 全尺寸图片幻灯片

图 8 催化剂的热重分析

Figure 8 Thermogravimetric curves of various catalysts

下载: 全尺寸图片幻灯片

图 9 催化剂的H₂-TPR谱图

Figure 9 H₂-TPR profiles of various catalyst

下载: 全尺寸图片幻灯片

图 10 催化剂的CO₂-TPD谱图

Figure 10 CO₂-TPD profiles of various catalysts

下载: 全尺寸图片幻灯片

图 11 催化剂的XPS光谱谱图

Figure 11 XPS spectra of various catalysts

下载: 全尺寸图片幻灯片

图 12 350 ℃下催化剂的原位红外光谱谱图

Figure 12 In-situ DRIFTS spectra of various catalysts for SO₂ oxidation at 350 °C

下载: 全尺寸图片幻灯片

表 1 实验所用标准气体

Table 1 The standard gas for the experiment

Gas	Purity	Producer
N₂	99.99%	Sizhi Gas Co. LTD, Tianjin
O₂	99.99%	Sizhi Gas Co. LTD, Tianjin
NO	5%	Sizhi Gas Co. LTD, Tianjin
NH₃	5%	Sizhi Gas Co. LTD, Tianjin
SO₂	5%	Haipu Gas Co. LTD, Beijing

下载: 导出CSV

表 2 样品的孔结构分析

Table 2 Textural properties of various catalysts

Catalyst	Surface area A/(m²·g⁻¹)	Pore volume v/(cm³·g⁻¹)	Pore size d/nm
V₂W₅/TiO₂	129.2	0.494	15.31
V₂W₅Nb₁/TiO₂	100.68	0.38	17.39
V₂W₅Nb₂/TiO₂	111.4	0.417	14.97
V₂W₅Nb₃/TiO₂	111.9	0.441	15.72

下载: 导出CSV

表 3 催化剂表面组成分析

Table 3 Surface composition of various catalyst determined by XPS

Catalyst	Surface atomic concentration / %					Surface atomic ratio / %
	O	V	Ti	W	Nb	V⁵⁺/（V⁵⁺+V⁴⁺）	O
	O	V	Ti	W	Nb	V⁵⁺/（V⁵⁺+V⁴⁺）	O_ß	O_α
V₂W₅/TiO₂	67.25	0.81	29.24	2.70	0	81.93	76.68	23.32
V₂W₅Nb₂/TiO₂	67.18	0.64	28.69	2.40	1.09	57.12	83.68	16.32

下载: 导出CSV

参考文献(40)

[1]	罗汉成, 潘卫国, 丁红蕾, 李付晓, 郭瑞堂, 金强, 丁承刚. 燃煤锅炉烟气中SO₃的产生机理及其控制技术[J]. 锅炉技术,2015,46(6):69−72. doi: 10.3969/j.issn.1672-4763.2015.06.015 LUO Hang-cheng, PAN Wei-guo, DING Hong-lei, LI Fu-xiao, GUO Rui-tang, JIN Qiang, DING Cheng-gang. Mechanism and control technology of SO₃ in flue gas of coal-fired boiler[J]. Boiler Technol,2015,46(6):69−72. doi: 10.3969/j.issn.1672-4763.2015.06.015
[2]	KAMATA H, OHARA H, TAKAHASHI K, YUKIMURA A, SEO Y. SO₂ oxidation over the V₂O₅/TiO₂ SCR catalyst[J]. Catal Lett,2001,73(1):79−83. doi: 10.1023/A:1009065030750
[3]	王飞. 燃煤电厂SO₃抑制与脱除技术综述[J]. 科技资讯,2019,31:150−151. WANG Fei. Review of SO₃ suppression and removal technologies in coal-fired power plants[J]. Sci Technol Inf,2019,31:150−151.
[4]	ZHANG Y, LAUMB J, LIGGETT R, HOLMES M, PAVLISH J. Impacts of acid gases on mercury oxidation cross SCR catalyst[J]. Fuel Process Technol,2007,88(10):929−934. doi: 10.1016/j.fuproc.2007.03.010
[5]	张道军, 马子然, 孙琦, 徐文强, 李永龙, 王宝东, 竹涛, 林德海, 季广辉, 马静. 硫酸氢氨在钒基选择性催化还原催化剂表面的生成、作用及防治[J]. 化工进展,2018,37(7):2635−2643. ZHANG Dao-jun, MA Zi-ran, SUN Qi, XU Wen-qiang, LI Yong-long, WANG Bao-dong, ZHU Tao, LIN De-hai, JI Guang-hui, MA Jing. Formation mechanism, effects and prevention of NH₄HSO₄ formed on the surface of V₂O₅ based catalysts[J]. Chem Ind Eng Prog,2018,37(7):2635−2643.
[6]	VEMOT E H, MACEWEN J D, HAUN C C, KINKEAD E R. Acute Toxicity and Skin Corrosion Data for Some Organic and Inorganic Compounds and Aqueous Solutions[J]. Toxicol Appl Pharmacol,1977,42(2):417−423. doi: 10.1016/0041-008X(77)90019-9
[7]	CHEN M M, JIN Q J, TAO X J, PAN Y C, GU S S, SHEN Y S. Novel W-Zr-O_x/TiO₂ catalyst for selective catalytic reduction of NO by NH₃ at high temperature[J]. Catal Today,2020,358:254−262. doi: 10.1016/j.cattod.2019.06.045
[8]	KOBAYASHI M, KUMA R, MASAKI S, SUGISHIMA N. TiO₂-SiO₂, and V₂O₅/TiO₂-SiO₂, catalyst: Physico-chemical characteristics and catalytic behavior in selective catalytic reduction of NO by NH₃[J]. Appl Catal B: Environ, 2005, 60(3/4): 173–179.
[9]	CHOO S T, YIM S D, NAM I S, HAM S W, LEE J B. Effect of promoters including WO₃ and BaO on the activity and durability of V₂O₅/sulfated TiO₂ catalyst for NO reduction by NH₃[J]. Appl Catal B: Environ,2003,44(3):237−252. doi: 10.1016/S0926-3373(03)00073-0
[10]	HOU Y Q, WANG J C, LI Q Y, LIU Y J, BAI Y R, ZENG Z Q, HUANG Z G. Environmental-friendly production of FeNbTi catalyst with significant enhancement in SCR activity and SO₂ resistance for NO_x removal[J]. Fuel,2021,285:119133. doi: 10.1016/j.fuel.2020.119133
[11]	CAO L, WU X D, CHEN Z, MA Y, MA Z R, RAN R, SI Z C, WENG D, WANG B D. A comprehensive study on sulfur tolerance of niobia modified CeO₂/WO₃-TiO₂ catalyst for low-temperature NH₃-SCR[J]. Appl Catal A: Gen,2019,580:121−130. doi: 10.1016/j.apcata.2019.05.007
[12]	SAZONOVA N N, TSYKOZA L T, SIMAKOV A V, BARANNIK G B, ISMAGILOV Z R. Relationship between sulfur dioxide oxidation and selective catalytic NO reduction by ammonia on V₂O₅-TiO₂ catalysts doped with WO₃, and Nb₂O₅[J]. React Kinet Catal Lett,1994,52(1):101−106. doi: 10.1007/BF02129856
[13]	AHN J, OKERLUND R, FRY A, EDDINGS E G. Sulfur trioxide formation during oxy-coal combustion[J]. Int J Greenhouse Gas Control,2011,5(12):127−135.
[14]	张翰之. SCR催化法中SO₂/SO₃转化率的影响因素研究[D]. 保定: 华北电力大学, 2018. ZHANG Han-zhi. Influencing Factors of SO₂/SO₃ conversion rate in SCR catalytic process[D]. Baoding: North China Electric Power University, 2018.
[15]	REDDY B M, KHAN A, YAMADA Y, KOBAYASHI T, LORIDANT S, VOLTA J C. Raman and X-ray photoelectron spectroscopy study of CeO₂-ZrO₂ and V₂O₅/CeO₂-ZrO₂ catalysts[J]. Langmuir,2003,19:3025−3030. doi: 10.1021/la0208528
[16]	刘智. SO₂在商用SCR催化剂表面氧化机理的研究[D]. 天津: 河北工业大学, 2019. LIU Zhi. Study on SO₂ oxidation mechanism on commercial SCR catalysts surface[D]. Tianjin: Hebei University of Technology, 2019.
[17]	KANG T A, YOUN S, KIM D H. Improved catalytic performance and resistance to SO₂ over V₂O₅-WO₃/TiO₂ catalyst physically mixed with Fe₂O₃ for low-temperature NH3-SCR[J]. Catal Today,2021,376:95−103. doi: 10.1016/j.cattod.2020.07.042
[18]	晁晶迪, 何洪, 宋丽云, 房玉娇, 梁全明, 张桂臻, 邱文革, 张然. Pr掺杂对V₂W₅-Mo₃/TiO₂催化剂NH₃-SCR反应活性的影响[J]. 高等学校化学学报,2015,36(3):523−530. CHAO Jing-di, HE Hong, SONG Li-yun, FANG Yu-jiao, LIANG Quan-ming, ZHANG Gui-zhen, QIU Wen-ge, ZHANG Ran. Promotional effect of Pr-doping on the NH₃-SCR activity over the V₂O₅-MoO₃/TiO₂ catalyst[J]. Chem J Chin Univ,2015,36(3):523−530.
[19]	ZHU L, ZHONG Z P, XUE J M, XU Y Y, WANG C H, WANG L X. NH₃-SCR performance and the resistance to SO₂ for Nb doped vanadium based catalyst at low temperatures[J]. J Environ Sci,2018,65:306−316. doi: 10.1016/j.jes.2017.06.033
[20]	LIAN Z, LIU F, HE H, LIU K. Nb-doped VO_x/CeO₂ catalyst for NH₃-SCR of NO_x at low temperatures[J]. RSC Adv,2015,5(47):37675−37681. doi: 10.1039/C5RA02752G
[21]	WACHS I E, BRIAND L E, JEHNG J M, BURCHAM L, GAO X T. Molecular structure and reactivity of the group V metal oxides[J]. Catal Today,2000,57:323−330. doi: 10.1016/S0920-5861(99)00343-0
[22]	MARSAL A, ROSSINYOL E, BIMBELA F, TELLEZ C, CORONAS J, CORENT A, MORANTE J R. Characterisation of LaOCl sensing materials using CO₂-TPD, XRD, TEM and XPS[J]. Sens Actuators, B,2005,109(1):38−43. doi: 10.1016/j.snb.2005.03.022
[23]	PI Z P, SHEN B X, ZHAO J G, LIU J C. CuO, CeO₂ modified Mg-Al spinel for removal of SO₂ from fluid catalytic cracking flue gas[J]. Ind Eng Chem Res,2015,54(43):10622−10628. doi: 10.1021/acs.iecr.5b02329
[24]	LEE K M, LIM Y H, JO Y M. Evaluation of moisture effect on low-level CO₂ adsorption by ion-exchanged zeolite[J]. Environ Technol,2012,33(1):77−84. doi: 10.1080/09593330.2011.551837
[25]	YU Y K, MIAO J F, HE C, CHEN J S, LI C, DOUTHWAITE M. The remarkable promotional effect of SO₂ on Pb-poisoned V₂W₅-WO₃/TiO₂ catalysts: An in-depth experimental and theoretical study[J]. Chem Eng J,2018,338:191−201. doi: 10.1016/j.cej.2018.01.031
[26]	BOUDALI L K, GHORBEL A, GRANGE P. Characterization and reactivity of WO₃-V₂O₅ supported on sulfated titanium pillared clay catalysts for the SCR-NO reaction[J]. Comptes Rendus Chim, 2009, 12(6/7): 779–786.
[27]	QING M X, SU S, WANG L L, LIU L J, XU K, HE L M, JUN X, HU S, WANG Y, XIANG J. Getting insight into the oxidation of SO₂ to SO₃ over V₂O₅-WO₃/TiO₂ catalysts: Reaction mechanism and effects of NO and NH3[J]. Chem Eng J,2019,361:1215−1224. doi: 10.1016/j.cej.2018.12.165
[28]	ZHANG Y S, MEI D Q, WANG T, WANG J W, GU Y Z, ZHANG Z L, ROMERO C E, PAN W P. In-situ capture of mercury in coal-fired power plants using high surface energy fly ash[J]. Environ Sci Technol,2019,53(13):7913−7920. doi: 10.1021/acs.est.9b01725
[29]	CAI W, ZHONG Q, ZHAO W, BU Y F. Focus on the modified CexZr_1−xO₂ with the rigid benzene-muti-carboxylate ligands and its catalysis in oxidation of NO[J]. Appl Catal B: Environ, 2014, 158–159: 258–268.
[30]	DU X S, DAO X, FU Y C, GAO F, LUO Z Y, CEN K F. The co-effect of Sb and Nb on the SCR performance of the V₂O₅/TiO₂ catalyst[J]. J Colloid Interface Sci,2012,368:406−412. doi: 10.1016/j.jcis.2011.11.026
[31]	GAO X, JIANG Y, ZHONG Y, LUO Z Y, CEN K F. The activity and characterization of CeO₂-TiO₂ catalysts prepared by the sol-gel method for selective catalytic reduction of NO with NH₃[J]. J Hazard Mater, 2010, 174(1/3): 734–739.
[32]	YE D, QU R, SONG H, GAO X, LUO Z Y, NI M J, CEN K F. New insights into the various decomposition and reactivity behaviors of NH₄HSO₄ with NO on V₂W₅/TiO₂ catalyst surfaces[J]. Chem Eng J,2016,283:846−854. doi: 10.1016/j.cej.2015.08.020
[33]	LIU Y M, SHU H, XU Q S, ZHANG Y H, YANG L J. FT-IR study of the SO₂ oxidation behavior in the selective catalytic reduction of NO with NH₃ over commercial catalysts[J]. J Fuel Chem Technol,2015,43(8):1018−1024. doi: 10.1016/S1872-5813(15)30030-X
[34]	WEI L, CUI S P, GUO H X, MA X Y, ZHANG L J. DRIFT and DFT study of cerium addition on SO₂ of manganese-based catalysts for low temperature SCR[J]. J Mol Catal A: Chem, 2016, 421: 102–108.
[35]	PAN S W, LUO H C, LI L, WEI Z L, HUANG B C. H₂O and SO₂ deactivation mechanism of MnOx/MWCNTs for low-temperature SCR of NO_x with NH₃[J]. J Mol Catal A: Chem, 2013, 377: 154–161.
[36]	QING M X, SU S, WANG L L, LIU L J, XU K, HE L M, JUN X, HU S, WANG Y, XIANG J. Getting insight into the oxidation of SO₂ to SO₃ over V₂O₅-WO₃/TiO₂ catalysts: Reaction mechanism and effects of NO and NH₃[J]. Chem Eng J, 2019, 361: 1215–1224.
[37]	JIN R B, LIU Y, WANG Y, CEN W L, WU Z B, WANG H Q, WENG X L. The role of cerium in the improved SO₂ tolerance for NO reduction with NH3 over Mn-Ce/TiO₂ catalyst at low temperature[J]. Appl Catal B: Environ, 2014, 148–149: 582-588.
[38]	翁诗甫, 徐怡庄. 傅里叶变换红外光谱分析[M]. 3版. 北京: 化学工业出版社, 2016. WENG Shi-fu, XU Yi-zhuang. Fourier Transform Infrared Spectroscopy Analysis[M]. 3rd ed. Beijing: Chemical Industry Press, 2016.
[39]	LI H L, WU C Y, LI Y, LI L Q, ZHAO Y C, ZHANG J Y. Impact of SO₂ on elemental mercury oxidation over CeO₂-TiO₂ catalyst[J]. Chem Eng J, 2013, 219: 319–326.
[40]	ULERSTAM M, JOHNSON M S, VOGT R, LJUNGSTROM E. DRIFTS and Kundsen cell study of the heterogeneous reactivity of SO₂ and NO₂ on mineral dust[J]. Atmos Chem Phys,2003,3:2043−2051. doi: 10.5194/acp-3-2043-2003