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参考文献 1
环境保护部科技标准司. 炼焦化学工业污染物排放标准: GB 16171-2012 [S]. 北京: 中国环境科学出版社, 2012.
参考文献 2
环境保护部科技标准司. 钢铁烧结、球团工业大气污染物排放标准: GB 28662-2012 [S]. 北京: 中国环境科学出版社, 2012.
参考文献 3
HEY Y, MICHAELE F, ZHUM H, et al. Influence of catalyst synthesis method on selective catalytic reduction (SCR) of NO by NH3 with V2O5-WO3/TiO2 catalysts [J]. Applied Catalysis B: Environmental, 2016, 193: 141-150.
参考文献 4
张亚平, 郭婉秋, 王龙飞, 等. V2O5/CeO2催化剂用于低温NH3-SCR的性能研究[J]. 催化学报, 2015, 36(10): 1701-1710.
参考文献 5
ZANGS, ZHANGG, QIUW, et al. Resistance to SO2 poisoning of V2O5/TiO2 -PILC catalyst for the selective catalytic reduction of NO by NH3 [J]. Chinese Journal of Catalysis, 2016, 37(6): 888-897.
参考文献 6
WANY, ZHAOW, YUT, et al. Ni-Mn bi-metal oxide catalysts for the low temperature SCR removal of NO with NH3[J]. Applied Catalysis B: Environmental, 2014, 148-149(6): 114-122.
参考文献 7
LIUJ, LIUJ, ZHAOZ H, et al. Synthesis of a chabazite‐supported copper catalyst with full mesopores for selective catalytic reduction of nitrogen oxides at low temperature [J]. Chinese Journal of Catalysis, 2016, 37(5): 750-759.
参考文献 8
ROYERS, DUPREZD, CANF, et al. Perovskites as substitutes of noble metals for heterogeneous catalysis: Dream or reality [J]. Chemical Reviews, 2014, 114(20): 10292-10368.
参考文献 9
王瑞, 归柯庭, 梁辉. Ce的掺杂对负载型催化剂LaMnO/赤铁矿脱硝性能的影响[J]. 化工进展, 2016, 35(S2): 192-199.
参考文献 10
QIK, XIEJ, FANGD, et al. Performance enhancement mechanism of Mn-based catalysts prepared under N2 for NOx removal: Evidence of the poor crystallization and oxidation of MnOx[J]. Chinese Journal of Catalysis, 2017, 38(5): 845-851.
参考文献 11
王明洪, 王亮亮, 刘俊, 等. 过渡金属对选择性催化还原脱硝CeO2@TiO2催化剂低温活性的促进作用[J]. 燃料化学学报, 2017, 45(4): 497-504.
参考文献 12
沈伯雄, 刘亭, 杨婷婷, 等. 低温SCR脱硝催化剂过渡金属氧化物改性及硫中毒失活机制研究[J]. 环境科学, 2009, 30(8): 2204-2209.
参考文献 13
JIANGB, YUEL, WUZ. Low-temperature selective catalytic reduction of NO on MnOx /TiO2 prepared by different methods[J]. Journal of Hazardous Materials, 2009, 162(2): 1249-1254.
参考文献 14
WANGZ H, LINF W, JINGS D, et al. Ceria substrate-oxide composite as catalyst for highly efficient catalytic oxidation of NO by O2[J]. Fuel, 2016, 166: 352-360.
参考文献 15
ZHANGY P, GUOW Q, XuH T, et al. Characterization and activity of V2O5-CeO2/TiO2-ZrO2 catalysts for NH3-selective catalytic reduction of NOx [J]. Chinese Journal of Catalysis, 2015, 36(10): 1701-1710.
参考文献 16
ZHANGJ X, ZHANGS L, CAIW, et al. Effect of chromium oxide as active site over TiO2-PILC for selective catalytic oxidation of NO [J]. Journal of Environmental Sciences, 2013, 25(12): 2492-2497.
参考文献 17
PAVULESCUV I, GRANGEP, DELMONB. Catalytic removal of NO [J]. Catalysis Today, 1998, 46: 233-316.
参考文献 18
李小海, 张舒乐, 贾勇, 等. H2O和SO2对Ce(1)Mn(3)Ti催化剂催化氧化NO性能的影响[J]. 燃料化学学报, 2012, 40(4): 866-871.
参考文献 19
LIL D, SHENQ, CHENGJ, et al. Catalytic oxidation of NO over TiO2 supported platinum clusters. Ⅱ: Mechanism study by situ FTIR spectra [J]. Catalysis Today, 2010, 158(3/4): 361-369.
参考文献 20
BONDG C. Vanadium oxide monolayer catalysts preparation characterization and catalytic activity [J]. Applied Catalysis, 1991, 71(1): 1-31.
参考文献 21
BUSCAG, CENTIG, TRIFIROF, et al. Surface acidity of vanadyl pyrophosphate active phase in n-butane selective oxidation [J]. Journal of Physical Chemistry, 1986, 90(7): 1337-1344.
参考文献 22
姜烨, 高翔, 吴卫红. H2O和SO2对V2O5/TiO2催化剂选择性催化还原烟气脱硝性能的影响[J]. 中国电机工程学报, 2013, 33(20): 28-33.
参考文献 23
段瑞瑞. V4+/V5+比值调变影响因素及其V4+和V5+转化的氧化还原速率与SCR脱硝活性[D]. 哈尔滨: 哈尔滨工程大学, 2014.
参考文献 24
FENGX Z, YAOY, SUQ, et al. Vanadium pyrophosphate oxides: The role of preparation chemistry in determining renewable acrolein production from glycerol dehydration [J]. Applied Catalysis B: Environmental, 2015, 164: 31-39.
参考文献 25
曾炜, 顾龙勤, 徐俊峰, 等. 不同P与V比的Mo/VPO催化剂物相组成及其催化性能[J]. 工业催化, 2014, 22(8): 595-598.
参考文献 26
TOPSØEN Y. Mechanism of the selective catalytic reduction of nitric oxide by ammonia elucidated by in situ on-line fourier transform infrared spectroscopy [J]. Science, 1994, 265(5176): 1217-1219.
参考文献 27
NOVAI, CIARDELLIC, TRONCONIE, et al. NH3-NO/NO2, chemistry over V-based catalysts and its role in the mechanism of the fast SCR reaction[J]. Catalysis Today, 2006, 114(1): 3-12.
参考文献 28
JIAY, DUD Q, BAIJ C, et al. Characterization and activity of N doped TiO2 supported VPO catalysts for NO oxidation [J]. Atmospheric Pollution Research, 2015, 6(2): 184-190.
参考文献 29
LIL D, SHENQ, CHENGJ, et al. Catalytic oxidation of NO over TiO2 supported platinum clusters. Ⅱ: Mechanism study by situ FTIR spectra[J]. Catalysis Today, 2010, 158(3/4): 361-369.
参考文献 30
GANL, GUOF, YUJ, et al. Improved low-temperature activity of V2O5-WO3/TiO2 for denitration using different vanadium precursors [J]. Catalysts, 2016, 6(2): 25-40.
参考文献 31
LINC H, BAIH. Surface acidity over vanadia/titania catalyst in the selective catalytic reduction for NO removal: In situ DRIFTS study [J]. Applied Catalysis B: Environmental, 2003, 42(3): 279-287.
参考文献 32
CHENT, GUANB, LINH, et al. In situ DRIFTS study of the mechanism of low temperature selective catalytic reduction over manganese-iron oxides [J]. Chinese Journal of Catalysis, 2014, 35(3): 294-301.
参考文献 33
CHIRRANJITS, SNEHAS, ANIRUDDHAM, et al. Synthesis, characterization of VPO catalyst dispersed on mesoporous silica surface and catalytic activity for cyclohexane oxidation reaction[J]. Microporous and Mesoporous Materials, 2016, 223: 121-128.
参考文献 34
GUOX Y, CALB, WILLIAMH, et al. Effects of sulfate species on V2O5/TiO2 SCR catalysts in coal and biomass-fired systems [J]. Applied Catalysis B: Environmental, 2009, 92(1/2): 30-40.
参考文献 35
CHENJ P, YANGR T. Selective catalytic reduction of NO with NH3 on SO42-/TiO2 superacid catalyst[J]. Journal of Catalysis, 1993, 139(1): 277-288.
参考文献 36
LUQ, PANGD, ZHANGC, et al. In situ IR studies of Co and Ce doped Mn/TiO2, catalyst for low-temperature selective catalytic reduction of NO with NH3 [J]. Applied Surface Science, 2015, 357(3): 189-196.
参考文献 37
NIEJ, WUX, MA Z, et al. Tailored temperature window of MnOx -CeO2, SCR catalyst by addition of acidic metal oxides [J]. Chinese Journal of Catalysis, 2014, 35(8): 1281-1288.
参考文献 38
CHENT, GUANB, LINH, et al. In situ DRIFTS study of the mechanism of low temperature selective catalytic reduction over manganese-iron oxides [J]. Chinese Journal of Catalysis, 2014, 35(3): 294-301.
目录 contents

    摘要

    针对目前低温脱硝催化剂抗硫抗水性较差的不足,以TiO2为载体负载活性组分V2O5,利用磷酸调控表面酸性,制备了磷酸氧钒催化剂VPO/TiO2,并实验研究了SO2和水蒸气对其脱硝活性的影响。结果表明:控制P与V的摩尔比为1/5,活性组分(VPO)负载量为10%,焙烧温度为400 ℃时,催化剂脱硝性能最好,180~400 ℃温度范围内脱硝率高于98%;反应温度为200 ℃,烟气中SO2体积分数为200×10-6~800×10-6和水蒸气体积分数为4%时,催化剂的活性无明显下降。添加磷酸能够促使催化剂表面生成VOPO4、(VO)2P2O7V4+/V5+氧化还原电对,提高了催化剂的低温脱硝活性。磷酸可增强催化剂的表面酸性,减少了SO2的表面吸附及其与活性组分的反应。另外,催化剂表面以介孔为主,可提高未被水分子占据的活性位点量,FT-IR图谱显示抗硫抗水测试后的VPO/TiO2表面未发现有硫酸根生成,VPO/TiO2表现出较强的抗SO2和水蒸气毒化的性能。负载型磷酸氧钒催化剂具有较高的脱硝活性和较强的抗硫抗水性能。

    Abstract

    In view of poor resistance to sulfur and water vapor for the low temperature DeNOx catalyst, a type of vanadium phosphate catalyst VPO/TiO2 was prepared through doping active constituent V2O5 on TiO2 and regulating the surface acidity with phosphoric acid in this study, and the effects of SO2 and water vapor on its DeNOx activity were studied. The results showed that the best DeNOx performance of this vanadium phosphate catalyst was obtained at P/V molar ratio of 1/5, 10% active component (VPO) loading and the calcination temperature of 400 ℃, and the corresponding DeNOx efficiency was above 98% at the temperature range of 180~400 ℃. The DeNOx efficiency didn’t decrease at reaction temperature of 200 ℃ when the volume fractions of SO2 and water vapor were 200×10-6~800×10-6 and 4%, respectively. The addition of phosphoric acid could promote the formation of VOPO4, (VO)2P2O7 and redox couples V4+/V5+, which led to the improvement on the low temperature DeNOx activity of the catalyst. Phosphoric acid addition could enhance the surface acidity of vanadium-based catalyst, suppressed SO2 adsorption on the catalyst surface and their reaction to active constituent. In addition, the catalyst surface mainly contained mesoporous structure, which caused the increase of the amount of active sites unoccupied by the water molecules. The FT-IR spectra show that sulfate was not produced on the surface of tested VPO/TiO2 in the presence of SO2 and water vapor. The VPO/TiO2 catalysts show a strong resistance to SO2 and water vapor. Accordingly, the supported vanadium phosphate catalyst in this study had a high catalytic activity and strong sulfur and water resistance.

    氮氧化物(NOx)是一种主要的大气污染物,能够引起酸雨、光化学烟雾和雾霾等。以焦炉烟气、烧结烟气为代表的工业烟气,是除燃煤烟气之外的又一重要NOx排放源。随着环保治理的大力推进,工业烟气脱硝势在必[1,2]。目前,选择性催化还原脱硝(SCR)技术是控制NOx排放的主要手段,V-W(Mo)/Ti是燃煤烟气脱硝中普遍商业化应用的催化[3]。尽管如此,炼焦、烧结等工业烟气的温度一般低于250 ℃,V-W(Mo)/Ti(最佳活性温度300~400 ℃)催化剂并不适[4,5]。因此,促进工业烟气脱硝进程的关键部分是低温催化剂的研发。

    目前,研究用作低温脱硝的催化剂的材料主要有活性炭、分子筛、贵金属和金属氧化物等,其中过渡金属氧化物因具有良好的催化活性、来源广和价格低等优点而成为低温脱硝催化剂的研究热[6,7,8]。王瑞[9]、QI[10]对制备的Mn、Ce基催化剂进行了低温性能测试,在200 ℃温度下脱硝率可达90%以上。王明洪[11]研究了不同过渡金属M(M =Mn、Co、Fe和Cu)掺杂改性CeO2@TiO2催化剂的低温活性,当反应温度为175 ℃时,制备的Cu-CeO2@TiO2催化剂的脱硝率可达95%,但未对其抗中毒能力进行考察。沈伯雄[12]对自行制备的MnOx-CeOx/ACF 催化剂进行了低温性能考察,当反应温度为230 ℃时,催化剂的脱硝率可达90%,在SO2通入10 h后,催化剂的活性下降到20%左右。JIANG[13]的研究表明,当烟气中SO2体积分数为200×10-6时,MnOx/TiO2催化剂的脱硝率从99%下降至60%。WANG[14]研究亦得出了类似结论。钒(V)因其具有良好的氧化还原和不易被硫酸盐化等特性,故常被相关研究用做脱硝催化剂活性组分。ZHANG[15]研究制备了V基脱硝催化剂,在反应温度160~300 ℃范围内,NOx的去除率大于90%。然而,催化剂的脱硝活性受SO2和水蒸气影响较大。SO2主要通过活性组分硫酸盐化和硫酸铵沉积引起催化剂活性下降,水蒸气主要通过物理吸附占据活性位点来降低催化剂的脱硝活[16]。活性组分的硫酸盐化为不可逆失活,硫酸铵的分解温度高于250 ℃,如何提高低温脱硝催化剂抗SO2、水蒸气毒化仍需进一步实验。目前,用于低温脱硝催化剂的研究,主要思路是采用不同的过渡金属氧化物及其组合或更换载体。

    PAVULESCU[17]研究指出,脱硝过程是还原剂NH3吸附在催化剂表面的Brønsted酸性位上,与气相中的NOx结合,并进一步分解成无害的N2。过渡金属氧化物表面通常具有能够提供质子或接受电子对的特性,即L酸(Lewis酸)和B酸(Brønsted酸),催化剂的表面酸性往往与催化反应活性及选择性密切相[18,19]。SO2是酸性气体,增强催化剂的表面酸性可减少SO2的表面吸附及其与活性组分的反应。BOND[20]在研究烷烃催化氧化时指出,在氧化钒催化剂的制备过程中加入磷酸,磷(P高电负性)使得 V―(O―P)键出现极化和诱导效应,不仅使得催化剂表面产生大量的B酸(P―OH),而且会在V4+中心形成较强的L酸性[21]

    催化剂表面存在水蒸气吸附-脱附平衡现象(任一温度下被水分子占据的活性位点占总活性位点的比例一定),因而通过增大催化剂比表面积来提高水蒸气存在条件下活性位点曝露数量是提高其抗水性能的一个思[22]。本研究以钒为活性组分,比表面积为328.52 m2·g-1的二氧化钛为载体,利用磷酸来调节表面酸性,制备不同条件下负载型钒磷氧催化剂(VPO/TiO2),并对其低温脱硝和抗硫抗水性能进行了实验研究。

  • 1 实验部分

    1
  • 1.1 催化剂的制备

    1.1

    称取2 g活性前驱物V2O5加入到8 mL苯甲醇(溶剂)和12 mL异丁醇(还原剂)的混合液中,并在150 ℃温度下回流3 h,再按磷、钒摩尔比加入一定量的磷酸(85%),继续回流2 h;然后,对反应后的混合物进行抽滤,得到的固体物质在105 ℃下烘干2 h后,在350~500 ℃温度下焙烧3 h得到活性组分VPO;接着采用浸渍法将活性组分VPO负载到大比表面积(328.52 m2·g-1)载体TiO2上(活性组分负载量为5%~15%),制备产生VPO/TiO2催化剂。

  • 1.2 活性测试

    1.2

    催化剂的脱硝活性测试在固定床催化反应装置内进行(内径为8 mm),工艺流程如图1所示。称取0.47 g催化剂置于反应器中部,所需钢瓶气(N2、NO、NH3O2、SO2)经减压阀后由质量流量计控制流量,在预热器(120 ℃)内混合、加热,后进入反应器内进行脱硝反应,其中N2为载气。实验过程中控制NO体积分数为500×10-6,NH3体积分数为500×10-6O2体积分数8 %,空速(GHSV)约15 000 h-1。利用微量蠕动泵(BT100-1F型)将一定量的蒸馏水加入到预热器中,蒸馏水蒸发为水蒸气并与其他气体在管路中混合。实验稳定2 h后,测量进、出口烟气中NOx浓度,避免因物理吸附造成实验误差。反应器分3段程序控温,每次升温均稳定1 h后开始测量。烟气中NOx浓度采用Vario Plus型烟气分析仪进行测量,NOx去除率按下式进行计算:

    Κ = C i n - C o u t C i n × 100 %
    (1)

    式中:K为NOx去除率,%;Cin为进口NOx体积分数;Cout为出口NOx体积分数。

    图1
                            固定床催化反应装置流程图

    图1 固定床催化反应装置流程图

    Fig.1 Diagram of a fixed bed for catalyst activity test

  • 1.3 催化剂表征

    1.3

    采用X-ray diffraction(北京普析通用XD-3型,Cu靶,扫描角度为5° ≤2θ ≤ 80°)测定催化剂的晶相结构;采用N2吸附脱附(北京金埃谱V-sorb2008P型)测定催化剂的比表面积及孔径大小,以N2为吸附气、He为载气,将样品预先在473 K下脱气处理12 h,以去除样品表面的吸附气;采用SEM(JEOLJSM-6380LV型)测试催化剂的微观形貌,测试电压为25 kV;采用FTIR Spectrometer(MB154S型)测试催化剂的表面官能团和表面酸性,以KBr作为载体,测定波数范围是50~4 000 cm-1

  • 2 结果与讨论

    2
  • 2.1 催化剂活性测试

    2.1
  • 2.1.1 磷、钒摩尔比的影响

    2.1.1

    控制VPO负载量10%,催化剂煅烧温度400 ℃,实验研究了不同磷、钒摩尔比(P/V)对催化剂VPO/TiO2脱硝活性的影响,结果如图2所示。从图2中可以看出,当P/V从1/1降低至1/5的过程中,脱硝效率呈上升趋势,P/V为1/5时催化剂的脱硝活性最好,180~250 ℃温度范围内的脱硝效率高于98%。此后,继续降低P/V,脱硝活性随之降低。原因可能在于,当P/V为1/5时,能够促使催化剂VPO/TiO2中形成较多的氧化还原电对V4+/V5+,低温条件下,催化剂表现出较强的去除NOx的能[23]

    图2
                            P/V对催化剂活性的影响

    图2 P/V对催化剂活性的影响

    Fig.2 Effect of P/V on catalytic activity of catalyst

    采用XRD衍射仪分别对P/V为1/4、1/5和1/6的活性组分表征,结果如图3所示。从图3可以看出,催化剂表面主要存在V2O5、VOPO4和(VO)2P2O7 3种物[24]。当P/V为1/5时,V2O5的特征衍射峰较P/V为1/6和1/4时的弱。这可能是因为当P/V为1/6时,与V2O5反应的H3PO4较少,生成的(VO)2P2O7的量相对较少。当P/V为1/4时,P物质在活性组分体相中富集,进而造成(VO)2P2O7的量下[25]。催化剂表面形成的活性晶相(VO)2P2O7(V4+)、VOPO4(V5+)中含有V―OH、P―OH 等Brønsted酸性位点,这为还原剂NH3提供了更多吸附位点,从而促进NO的活化去除;另外,不同价态的活性晶相(VO)2P2O7(V4+)、VOPO4(V5+)会形成V5+/V4+离子对,催化剂表面的V4+V5+主要以V―OH、V == O形式存在,烟气中的NO被氧化成为NO2,同时V5+ == O被还原成V4+―OH,促进“快速SCR”反应的进行,进而提高催化剂的低温活[26,27,28,29,30]。此外,从图2中还可以看出,反应温度在250~400 ℃范围内,催化剂的脱硝效率稳定在98%以上。

    图3
                            不同P/V催化剂的XRD图谱

    图3 不同P/V催化剂的XRD图谱

    Fig.3 XRD patterns of low temperature catalysts with different P/V

  • 2.1.2 活性组分负载量的影响

    2.1.2

    控制P/V为1/5,催化剂焙烧温度为400 ℃,实验研究了活性组分V(5)PO负载量对催化剂V(5)PO/TiO2脱硝活性的影响,结果如图4所示。从图4中可以看出,温度在180~200 ℃范围内,活性组分为10%的催化剂脱硝活性最好。反应温度为180 ℃时,当V(5)PO负载量由5%增加至10%时,催化剂的脱硝率从40%增加到98%,此后继续增加V(5)PO负载量到15%,脱硝率下降至95%。其原因可能在于,当V(5)PO负载量为5%时活性组分在载体表面未形成均匀分布;当V(5)PO负载量为15%时,活性组分在催化剂表面聚集,造成部分孔道堵[31]。为了证实该推测,分别测试VPO负载量为5%、10%和15%的催化剂的比表面积和孔径分布,结果如图5和表1所示。从图5中可以看出,V(5)PO负载量分别为5%、10%和15%的等温吸附脱附曲线均出现了H3滞后[32],V(5)PO负载量为10%的催化剂出现了明显的介孔聚集区,这与表1中的比表面积测试数据相吻合。

    图4
                            VPO负载量对催化剂脱硝活性的影响

    图4 VPO负载量对催化剂脱硝活性的影响

    Fig.4 Effect of VPO load on DeNOx activity of catalyst

    图5
                            V(5)PO/TiO2等温吸附脱附曲线和孔径分布

    图5 V(5)PO/TiO2等温吸附脱附曲线和孔径分布

    Fig.5 Adsorption-desorption isotherm and pore size distribution of V(5)PO/TiO2

  • 表1 不同VPO负载量的催化剂比表面积

    Table 1 Specific surface area of catalysts at different VPO loading

    催化剂比表面积/(m2·g-1孔容/(cm3·g-1平均孔径/nm
    5%V(5)PO/TiO2122.980.375.40
    10%V(5)PO/TiO2153.050.356.40
    15%V(5)PO/TiO2168.720.385.80
  • 2.1.3 煅烧温度的影响

    2.1.3

    控制P/V为1/5,VPO负载量为10%,实验测试了焙烧温度对催化剂低温脱硝活性的影响,结果如图6所示。从图6中可以看出,400 ℃温度下焙烧的VPO/TiO2催化剂脱硝活性较350 ℃和450 ℃温度下焙烧的催化剂高。对不同温度焙烧的VPO/TiO2进行XRD测试,结果显示,400 ℃温度下焙烧的VPO/TiO2催化剂的结晶度较350 ℃温度焙烧的催化剂高。其原因可能:当焙烧温度为350 ℃时活性组分未形成有效的活性晶相。表 2的BET测试结果表明,控制焙烧温度为450 ℃时,催化剂的比表面积(117.70 m2·g-1)较400 ℃温度下焙烧催化剂的小23.1%,这与图6中的活性测试结果相吻合。

    图6
                            焙烧温度对催化剂脱硝活性的影响

    图6 焙烧温度对催化剂脱硝活性的影响

    Fig.6 Effect of calcination temperature on DeNOx efficiency of catalyst

    表2 不同煅烧温度下VPO/TiO2的比表面积

    Table 2 Specific surface area of VPO/TiO2 calcined at different temperature

    煅烧温度/℃比表面积/(m2·g-1)孔容/(cm3·g-1)平均孔径/nm
    350160.370.385.90
    400153.050.366.40
    450117.660.365.80

    7(a)、(b)和(c)分别为350、400和450 ℃温度焙烧催化剂VPO/TiO2的SEM图。从图7中可以看出,350 ℃温度下焙烧的催化剂呈不规则块状,400 ℃温度焙烧下的催化剂呈颗粒状且粒径分布较均匀,当煅烧温度达到450 ℃时,催化剂出现烧结现象,且团聚现象明显。这进一步解释了图6中的活性测试结果。

    图7
                            不同煅烧温度下VPO/TiO2的SEM图谱

    图7 不同煅烧温度下VPO/TiO2的SEM图谱

    Fig.7 SEM images of catalyst calcined at different temperature

  • 2.2 催化剂抗硫抗水性能测试

    2.2

    上述实验结果表明,10%V(5)PO/TiO2催化剂在400 ℃温度下煅烧制备条件下脱硝活性最好。以该催化剂为研究对象,向模拟烟气中通入SO2和水蒸气,控制烟气中SO2体积分数为200×10-6~800×10-6,水蒸气体积分数为4%,反应测试温度为200 ℃,考察了SO2和水蒸气对催化剂脱硝性能的影响,结果如图8所示。从图8中可以看出,烟气中水蒸气体积分数4%,SO2体积分数200×10-6~400×10-6时,催化剂的脱硝率为98%,450 min内没有下降;当水蒸气体积分数为4%,SO2体积分数为600×10-6~800×10-6时,催化剂的脱硝率在50 min后开始下降,到300 min下降至最低的40%;此后,停止通入SO2和水蒸气,催化剂的脱硝活性又逐步恢复到未通SO2和水蒸气时的水平。反应前后FT-IR测试催化剂,结果如图9所示。从图9中可以看出,催化剂反应前后的FT-IR图谱没有明显差别,3 430 cm-1和 1 635 cm-1处为H2O的伸缩振动[33],1 051 cm-1归属为V5+ == O的不对称伸缩振动[34],催化剂表面未发现有硫酸根的特征峰(1 190 cm-1、900 cm-1附近)[35],说明催化剂表面无硫酸铵沉积,且活性组分未被硫酸盐化。关于图8中的实验结果,其原因可能在于,当烟气中SO2浓度较高时,SO2和NH3在管道中反应生成(NH4)2SO3的推动力增强,导致进入反应器内还原剂NH3减少,使催化剂的低温脱硝活性下降。

    图8
                            SO2和水蒸气对10%V(5)PO/TiO2脱硝活性的影响

    图8 SO2和水蒸气对10%V(5)PO/TiO2脱硝活性的影响

    Fig.8 Effect of SO2 and H2O on DeNOx efficiency of 10%V (5) PO/TiO2

    图9
                            抗硫抗水测试前后10%V(5)PO/TiO2 的FT-IR谱图

    图9 抗硫抗水测试前后10%V(5)PO/TiO2 的FT-IR谱图

    Fig.9 FT-IR spectra of 10%V (5) PO/TiO2 before and after test with SO2 and H2O in feed gas

    为了证实上述推测,控制烟气中SO2体积分数为800×10-6,水蒸气体积分数为4%,在预热器与反应器之间的不锈钢管道上缠绕电加热带,加热温度为120 ℃,抑制管道中(NH4)2SO3((NH4)2SO3分解温度约60 ℃)的生成,并测试其脱硝活性,结果如图10所示。从图10中可以看出,催化剂的脱硝活性在反应时间为450 min内未下降,证实了上述推测。

    图10
                            SO2和水蒸气对10%V(5)PO/TiO2脱硝活性的影响(管道温度120 ℃)

    图10 SO2和水蒸气对10%V(5)PO/TiO2脱硝活性的影响(管道温度120 ℃)

    Fig.10 Effect of SO2 and H2O on DeNOx efficiency of 10%V (5) PO/TiO2 (pipe temperature 120 ℃)

    用NH3-IR测试不同P/V催化剂的表面酸性,结果如图11所示。从图11中的NH3-IR图谱可以看出,波数1 400 cm-1和1 630 cm-1处的特征峰可归属于V―OH或P―OH形成的Brønsted[36,37],波数3 160、3 253和3 334 cm-1可归属于Lewis酸(V == O)的特征[38]。图11同时表明,当P/V从0增加到1/5的过程中,Brønsted酸强度呈现逐渐增强的趋势,此后继续增加P/V到1/1,Brønsted酸的强度则呈减弱趋势。这可能是因为,当P/V小于1/5时,催化剂表面形成的P―OH相对较少,当P/V高于1/5时,催化剂表面生成较多的P―O―P和V―O―P,进而导致V―OH和P―OH的数量减少。

    图11
                            不同P/V摩尔比的NH3-IR谱图

    图11 不同P/V摩尔比的NH3-IR谱图

    Fig.11 NH3-IR spectra of different P/V mole ratio

    另外,10% V(5)PO/TiO2具有较强的表面酸性,可抑制SO2吸附,SO2若没有在催化剂作用下很难氧化成为SO3,因而催化剂表面没有(NH4)2SO4生成(图9);由于(NH4)2SO3的分解温度(60 ℃)远低于本研究脱硝反应温度,因而脱硝过程中也不会生成(NH4)2SO3,这与抗硫抗水活性测试及FT-IR测试结果相吻合,即催化剂10% V(5)PO/TiO2呈现出较强的抗硫抗水性能。

  • 3 结论

    3

    1) 以钒为活性组分,比表面积328.52 m2·g-1的二氧化钛为载体,用H3PO4调控催化剂表面酸性,并测试其低温脱硝能力。结果表明:控制催化剂P/V在1/5,VPO负载量在10%,焙烧温度在400 ℃的制备条件下脱硝性能最佳,测试反应温度在180~400 ℃,催化剂的脱硝率高于98%。

    2) 以钒为活性组分,添加磷酸可在催化剂表面生成VOPO4和(VO2)2P2O7,促使V4+/V5+氧化还原电对的形成,从而提高催化剂的低温活性;催化剂10%V(5)PO/TiO2表面孔径分布以介孔为主。

    3) 对催化剂10%V(5)PO/TiO2进行的抗硫抗水性能测试结果表明,当烟气中水蒸气体积分数为4%,SO2体积分数为200×10-6~800×10-6时,催化剂脱硝率稳定在98%左右,450 min内没有下降;FT-IR测试结果显示,反应后的催化剂表面未发现硫酸根:NH3-IR测试结果表明,在控制P/V为1/5的条件下,催化剂的表面酸性最强,有效抑制了活性组分的硫酸盐化和硫酸铵的生成,催化剂表现出较强的抗硫抗水性能。

  • 参 考 文 献

    • 1

      环境保护部科技标准司. 炼焦化学工业污染物排放标准: GB 16171-2012 [S]. 北京: 中国环境科学出版社, 2012.

    • 2

      环境保护部科技标准司. 钢铁烧结、球团工业大气污染物排放标准: GB 28662-2012 [S]. 北京: 中国环境科学出版社, 2012.

    • 3

      HE Y Y, MICHAEL E F, ZHU M H, et al. Influence of catalyst synthesis method on selective catalytic reduction (SCR) of NO by NH3 with V2O5-WO3/TiO2 catalysts [J]. Applied Catalysis B: Environmental, 2016, 193: 141-150.

    • 4

      张亚平, 郭婉秋, 王龙飞, 等. V2O5/CeO2催化剂用于低温NH3-SCR的性能研究[J]. 催化学报, 2015, 36(10): 1701-1710.

    • 5

      ZANG S, ZHANG G, QIU W, et al. Resistance to SO2 poisoning of V2O5/TiO2 -PILC catalyst for the selective catalytic reduction of NO by NH3 [J]. Chinese Journal of Catalysis, 2016, 37(6): 888-897.

    • 6

      WAN Y, ZHAO W, YU T, et al. Ni-Mn bi-metal oxide catalysts for the low temperature SCR removal of NO with NH3[J]. Applied Catalysis B: Environmental, 2014, 148-149(6): 114-122.

    • 7

      LIU J, LIU J, ZHAO Z H, et al. Synthesis of a chabazite‐supported copper catalyst with full mesopores for selective catalytic reduction of nitrogen oxides at low temperature [J]. Chinese Journal of Catalysis, 2016, 37(5): 750-759.

    • 8

      ROYER S, DUPREZ D, CAN F, et al. Perovskites as substitutes of noble metals for heterogeneous catalysis: Dream or reality [J]. Chemical Reviews, 2014, 114(20): 10292-10368.

    • 9

      王瑞, 归柯庭, 梁辉. Ce的掺杂对负载型催化剂LaMnO/赤铁矿脱硝性能的影响[J]. 化工进展, 2016, 35(S2): 192-199.

    • 10

      QI K, XIE J, FANG D, et al. Performance enhancement mechanism of Mn-based catalysts prepared under N2 for NOx removal: Evidence of the poor crystallization and oxidation of MnOx[J]. Chinese Journal of Catalysis, 2017, 38(5): 845-851.

    • 11

      王明洪, 王亮亮, 刘俊, 等. 过渡金属对选择性催化还原脱硝CeO2@TiO2催化剂低温活性的促进作用[J]. 燃料化学学报, 2017, 45(4): 497-504.

    • 12

      沈伯雄, 刘亭, 杨婷婷, 等. 低温SCR脱硝催化剂过渡金属氧化物改性及硫中毒失活机制研究[J]. 环境科学, 2009, 30(8): 2204-2209.

    • 13

      JIANG B, YUE L, WU Z. Low-temperature selective catalytic reduction of NO on MnOx /TiO2 prepared by different methods[J]. Journal of Hazardous Materials, 2009, 162(2): 1249-1254.

    • 14

      WANG Z H, LIN F W, JING S D, et al. Ceria substrate-oxide composite as catalyst for highly efficient catalytic oxidation of NO by O2[J]. Fuel, 2016, 166: 352-360.

    • 15

      ZHANG Y P, GUO W Q, Xu H T, et al. Characterization and activity of V2O5-CeO2/TiO2-ZrO2 catalysts for NH3-selective catalytic reduction of NOx [J]. Chinese Journal of Catalysis, 2015, 36(10): 1701-1710.

    • 16

      ZHANG J X, ZHANG S L, CAI W, et al. Effect of chromium oxide as active site over TiO2-PILC for selective catalytic oxidation of NO [J]. Journal of Environmental Sciences, 2013, 25(12): 2492-2497.

    • 17

      PAVULESCU V I, GRANGE P, DELMON B. Catalytic removal of NO [J]. Catalysis Today, 1998, 46: 233-316.

    • 18

      李小海, 张舒乐, 贾勇, 等. H2O和SO2对Ce(1)Mn(3)Ti催化剂催化氧化NO性能的影响[J]. 燃料化学学报, 2012, 40(4): 866-871.

    • 19

      LI L D, SHEN Q, CHENG J, et al. Catalytic oxidation of NO over TiO2 supported platinum clusters. Ⅱ: Mechanism study by situ FTIR spectra [J]. Catalysis Today, 2010, 158(3/4): 361-369.

    • 20

      BOND G C. Vanadium oxide monolayer catalysts preparation characterization and catalytic activity [J]. Applied Catalysis, 1991, 71(1): 1-31.

    • 21

      BUSCA G, CENTI G, TRIFIRO F, et al. Surface acidity of vanadyl pyrophosphate active phase in n-butane selective oxidation [J]. Journal of Physical Chemistry, 1986, 90(7): 1337-1344.

    • 22

      姜烨, 高翔, 吴卫红. H2O和SO2对V2O5/TiO2催化剂选择性催化还原烟气脱硝性能的影响[J]. 中国电机工程学报, 2013, 33(20): 28-33.

    • 23

      段瑞瑞. V4+/V5+比值调变影响因素及其V4+和V5+转化的氧化还原速率与SCR脱硝活性[D]. 哈尔滨: 哈尔滨工程大学, 2014.

    • 24

      FENG X Z, YAO Y, SU Q, et al. Vanadium pyrophosphate oxides: The role of preparation chemistry in determining renewable acrolein production from glycerol dehydration [J]. Applied Catalysis B: Environmental, 2015, 164: 31-39.

    • 25

      曾炜, 顾龙勤, 徐俊峰, 等. 不同P与V比的Mo/VPO催化剂物相组成及其催化性能[J]. 工业催化, 2014, 22(8): 595-598.

    • 26

      TOPSØE N Y. Mechanism of the selective catalytic reduction of nitric oxide by ammonia elucidated by in situ on-line fourier transform infrared spectroscopy [J]. Science, 1994, 265(5176): 1217-1219.

    • 27

      NOVA I, CIARDELLI C, TRONCONI E, et al. NH3-NO/NO2, chemistry over V-based catalysts and its role in the mechanism of the fast SCR reaction[J]. Catalysis Today, 2006, 114(1): 3-12.

    • 28

      JIA Y, DU D Q, BAI J C, et al. Characterization and activity of N doped TiO2 supported VPO catalysts for NO oxidation [J]. Atmospheric Pollution Research, 2015, 6(2): 184-190.

    • 29

      LI L D, SHEN Q, CHENG J, et al. Catalytic oxidation of NO over TiO2 supported platinum clusters. Ⅱ: Mechanism study by situ FTIR spectra[J]. Catalysis Today, 2010, 158(3/4): 361-369.

    • 30

      GAN L, GUO F, YU J, et al. Improved low-temperature activity of V2O5-WO3/TiO2 for denitration using different vanadium precursors [J]. Catalysts, 2016, 6(2): 25-40.

    • 31

      LIN C H, BAI H. Surface acidity over vanadia/titania catalyst in the selective catalytic reduction for NO removal: In situ DRIFTS study [J]. Applied Catalysis B: Environmental, 2003, 42(3): 279-287.

    • 32

      CHEN T, GUAN B, LIN H, et al. In situ DRIFTS study of the mechanism of low temperature selective catalytic reduction over manganese-iron oxides [J]. Chinese Journal of Catalysis, 2014, 35(3): 294-301.

    • 33

      CHIRRANJIT S, SNEHA S, ANIRUDDHA M, et al. Synthesis, characterization of VPO catalyst dispersed on mesoporous silica surface and catalytic activity for cyclohexane oxidation reaction[J]. Microporous and Mesoporous Materials, 2016, 223: 121-128.

    • 34

      GUO X Y, CAL B, WILLIAM H, et al. Effects of sulfate species on V2O5/TiO2 SCR catalysts in coal and biomass-fired systems [J]. Applied Catalysis B: Environmental, 2009, 92(1/2): 30-40.

    • 35

      CHEN J P, YANG R T. Selective catalytic reduction of NO with NH3 on SO42-/TiO2 superacid catalyst[J]. Journal of Catalysis, 1993, 139(1): 277-288.

    • 36

      LU Q, PANG D, ZHANG C, et al. In situ IR studies of Co and Ce doped Mn/TiO2, catalyst for low-temperature selective catalytic reduction of NO with NH3 [J]. Applied Surface Science, 2015, 357(3): 189-196.

    • 37

      NIE J, WU X, MA Z, et al. Tailored temperature window of MnOx -CeO2, SCR catalyst by addition of acidic metal oxides [J]. Chinese Journal of Catalysis, 2014, 35(8): 1281-1288.

    • 38

      CHEN T, GUAN B, LIN H, et al. In situ DRIFTS study of the mechanism of low temperature selective catalytic reduction over manganese-iron oxides [J]. Chinese Journal of Catalysis, 2014, 35(3): 294-301.

贾勇

机 构:

1. 安徽工业大学能源与环境学院,马鞍山 243002

2. 冶金减排与资源综合利用教育部重点实验室,马鞍山 243002

Affiliation:

1. School of Energy and Environment, Anhui University of Technology, Maanshan 243002, China

2. Metallurgical Emission Reduction & Resource Recycling, Ministry of Education, Maanshan 243002, China

角 色:第一作者

角 色:通讯作者

Role:First author

Role:Corresponding author

邮 箱:jiayong2000@163.com

第一作者简介:贾勇(1981— ),男,博士研究生,副教授。研究方向:大气污染控制。E-mail:jiayong2000@163.com

张松

机 构:安徽工业大学能源与环境学院,马鞍山 243002

Affiliation:School of Energy and Environment, Anhui University of Technology, Maanshan 243002, China

戴波

机 构:安徽工业大学能源与环境学院,马鞍山 243002

Affiliation:School of Energy and Environment, Anhui University of Technology, Maanshan 243002, China

顾明言

机 构:安徽工业大学能源与环境学院,马鞍山 243002

Affiliation:School of Energy and Environment, Anhui University of Technology, Maanshan 243002, China

史德明

机 构:安徽欣创节能环保科技股份有限公司,马鞍山 243071

Affiliation:Anhui Xinchuang Energy & Environmental Protection Science & Techmology Co. Ltd., Maanshan 243071, China

夏勇军

机 构:安徽欣创节能环保科技股份有限公司,马鞍山 243071

Affiliation:Anhui Xinchuang Energy & Environmental Protection Science & Techmology Co. Ltd., Maanshan 243071, China

胡笳

机 构:安徽欣创节能环保科技股份有限公司,马鞍山 243071

Affiliation:Anhui Xinchuang Energy & Environmental Protection Science & Techmology Co. Ltd., Maanshan 243071, China

金曙光,郑晓梅,张利田

角 色:中文编辑

Role:Editor

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催化剂比表面积/(m2·g-1孔容/(cm3·g-1平均孔径/nm
5%V(5)PO/TiO2122.980.375.40
10%V(5)PO/TiO2153.050.356.40
15%V(5)PO/TiO2168.720.385.80
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煅烧温度/℃比表面积/(m2·g-1)孔容/(cm3·g-1)平均孔径/nm
350160.370.385.90
400153.050.366.40
450117.660.365.80
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图1 固定床催化反应装置流程图

Fig.1 Diagram of a fixed bed for catalyst activity test

图2 P/V对催化剂活性的影响

Fig.2 Effect of P/V on catalytic activity of catalyst

图3 不同P/V催化剂的XRD图谱

Fig.3 XRD patterns of low temperature catalysts with different P/V

表1 不同VPO负载量的催化剂比表面积

Table 1 Specific surface area of catalysts at different VPO loading

图4 VPO负载量对催化剂脱硝活性的影响

Fig.4 Effect of VPO load on DeNOx activity of catalyst

图5 V(5)PO/TiO2等温吸附脱附曲线和孔径分布

Fig.5 Adsorption-desorption isotherm and pore size distribution of V(5)PO/TiO2

图6 焙烧温度对催化剂脱硝活性的影响

Fig.6 Effect of calcination temperature on DeNOx efficiency of catalyst

表2 不同煅烧温度下VPO/TiO2的比表面积

Table 2 Specific surface area of VPO/TiO2 calcined at different temperature

图7 不同煅烧温度下VPO/TiO2的SEM图谱

Fig.7 SEM images of catalyst calcined at different temperature

图8 SO2和水蒸气对10%V(5)PO/TiO2脱硝活性的影响

Fig.8 Effect of SO2 and H2O on DeNOx efficiency of 10%V (5) PO/TiO2

图9 抗硫抗水测试前后10%V(5)PO/TiO2 的FT-IR谱图

Fig.9 FT-IR spectra of 10%V (5) PO/TiO2 before and after test with SO2 and H2O in feed gas

图10 SO2和水蒸气对10%V(5)PO/TiO2脱硝活性的影响(管道温度120 ℃)

Fig.10 Effect of SO2 and H2O on DeNOx efficiency of 10%V (5) PO/TiO2 (pipe temperature 120 ℃)

图11 不同P/V摩尔比的NH3-IR谱图

Fig.11 NH3-IR spectra of different P/V mole ratio

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  • 参 考 文 献

    • 1

      环境保护部科技标准司. 炼焦化学工业污染物排放标准: GB 16171-2012 [S]. 北京: 中国环境科学出版社, 2012.

    • 2

      环境保护部科技标准司. 钢铁烧结、球团工业大气污染物排放标准: GB 28662-2012 [S]. 北京: 中国环境科学出版社, 2012.

    • 3

      HE Y Y, MICHAEL E F, ZHU M H, et al. Influence of catalyst synthesis method on selective catalytic reduction (SCR) of NO by NH3 with V2O5-WO3/TiO2 catalysts [J]. Applied Catalysis B: Environmental, 2016, 193: 141-150.

    • 4

      张亚平, 郭婉秋, 王龙飞, 等. V2O5/CeO2催化剂用于低温NH3-SCR的性能研究[J]. 催化学报, 2015, 36(10): 1701-1710.

    • 5

      ZANG S, ZHANG G, QIU W, et al. Resistance to SO2 poisoning of V2O5/TiO2 -PILC catalyst for the selective catalytic reduction of NO by NH3 [J]. Chinese Journal of Catalysis, 2016, 37(6): 888-897.

    • 6

      WAN Y, ZHAO W, YU T, et al. Ni-Mn bi-metal oxide catalysts for the low temperature SCR removal of NO with NH3[J]. Applied Catalysis B: Environmental, 2014, 148-149(6): 114-122.

    • 7

      LIU J, LIU J, ZHAO Z H, et al. Synthesis of a chabazite‐supported copper catalyst with full mesopores for selective catalytic reduction of nitrogen oxides at low temperature [J]. Chinese Journal of Catalysis, 2016, 37(5): 750-759.

    • 8

      ROYER S, DUPREZ D, CAN F, et al. Perovskites as substitutes of noble metals for heterogeneous catalysis: Dream or reality [J]. Chemical Reviews, 2014, 114(20): 10292-10368.

    • 9

      王瑞, 归柯庭, 梁辉. Ce的掺杂对负载型催化剂LaMnO/赤铁矿脱硝性能的影响[J]. 化工进展, 2016, 35(S2): 192-199.

    • 10

      QI K, XIE J, FANG D, et al. Performance enhancement mechanism of Mn-based catalysts prepared under N2 for NOx removal: Evidence of the poor crystallization and oxidation of MnOx[J]. Chinese Journal of Catalysis, 2017, 38(5): 845-851.

    • 11

      王明洪, 王亮亮, 刘俊, 等. 过渡金属对选择性催化还原脱硝CeO2@TiO2催化剂低温活性的促进作用[J]. 燃料化学学报, 2017, 45(4): 497-504.

    • 12

      沈伯雄, 刘亭, 杨婷婷, 等. 低温SCR脱硝催化剂过渡金属氧化物改性及硫中毒失活机制研究[J]. 环境科学, 2009, 30(8): 2204-2209.

    • 13

      JIANG B, YUE L, WU Z. Low-temperature selective catalytic reduction of NO on MnOx /TiO2 prepared by different methods[J]. Journal of Hazardous Materials, 2009, 162(2): 1249-1254.

    • 14

      WANG Z H, LIN F W, JING S D, et al. Ceria substrate-oxide composite as catalyst for highly efficient catalytic oxidation of NO by O2[J]. Fuel, 2016, 166: 352-360.

    • 15

      ZHANG Y P, GUO W Q, Xu H T, et al. Characterization and activity of V2O5-CeO2/TiO2-ZrO2 catalysts for NH3-selective catalytic reduction of NOx [J]. Chinese Journal of Catalysis, 2015, 36(10): 1701-1710.

    • 16

      ZHANG J X, ZHANG S L, CAI W, et al. Effect of chromium oxide as active site over TiO2-PILC for selective catalytic oxidation of NO [J]. Journal of Environmental Sciences, 2013, 25(12): 2492-2497.

    • 17

      PAVULESCU V I, GRANGE P, DELMON B. Catalytic removal of NO [J]. Catalysis Today, 1998, 46: 233-316.

    • 18

      李小海, 张舒乐, 贾勇, 等. H2O和SO2对Ce(1)Mn(3)Ti催化剂催化氧化NO性能的影响[J]. 燃料化学学报, 2012, 40(4): 866-871.

    • 19

      LI L D, SHEN Q, CHENG J, et al. Catalytic oxidation of NO over TiO2 supported platinum clusters. Ⅱ: Mechanism study by situ FTIR spectra [J]. Catalysis Today, 2010, 158(3/4): 361-369.

    • 20

      BOND G C. Vanadium oxide monolayer catalysts preparation characterization and catalytic activity [J]. Applied Catalysis, 1991, 71(1): 1-31.

    • 21

      BUSCA G, CENTI G, TRIFIRO F, et al. Surface acidity of vanadyl pyrophosphate active phase in n-butane selective oxidation [J]. Journal of Physical Chemistry, 1986, 90(7): 1337-1344.

    • 22

      姜烨, 高翔, 吴卫红. H2O和SO2对V2O5/TiO2催化剂选择性催化还原烟气脱硝性能的影响[J]. 中国电机工程学报, 2013, 33(20): 28-33.

    • 23

      段瑞瑞. V4+/V5+比值调变影响因素及其V4+和V5+转化的氧化还原速率与SCR脱硝活性[D]. 哈尔滨: 哈尔滨工程大学, 2014.

    • 24

      FENG X Z, YAO Y, SU Q, et al. Vanadium pyrophosphate oxides: The role of preparation chemistry in determining renewable acrolein production from glycerol dehydration [J]. Applied Catalysis B: Environmental, 2015, 164: 31-39.

    • 25

      曾炜, 顾龙勤, 徐俊峰, 等. 不同P与V比的Mo/VPO催化剂物相组成及其催化性能[J]. 工业催化, 2014, 22(8): 595-598.

    • 26

      TOPSØE N Y. Mechanism of the selective catalytic reduction of nitric oxide by ammonia elucidated by in situ on-line fourier transform infrared spectroscopy [J]. Science, 1994, 265(5176): 1217-1219.

    • 27

      NOVA I, CIARDELLI C, TRONCONI E, et al. NH3-NO/NO2, chemistry over V-based catalysts and its role in the mechanism of the fast SCR reaction[J]. Catalysis Today, 2006, 114(1): 3-12.

    • 28

      JIA Y, DU D Q, BAI J C, et al. Characterization and activity of N doped TiO2 supported VPO catalysts for NO oxidation [J]. Atmospheric Pollution Research, 2015, 6(2): 184-190.

    • 29

      LI L D, SHEN Q, CHENG J, et al. Catalytic oxidation of NO over TiO2 supported platinum clusters. Ⅱ: Mechanism study by situ FTIR spectra[J]. Catalysis Today, 2010, 158(3/4): 361-369.

    • 30

      GAN L, GUO F, YU J, et al. Improved low-temperature activity of V2O5-WO3/TiO2 for denitration using different vanadium precursors [J]. Catalysts, 2016, 6(2): 25-40.

    • 31

      LIN C H, BAI H. Surface acidity over vanadia/titania catalyst in the selective catalytic reduction for NO removal: In situ DRIFTS study [J]. Applied Catalysis B: Environmental, 2003, 42(3): 279-287.

    • 32

      CHEN T, GUAN B, LIN H, et al. In situ DRIFTS study of the mechanism of low temperature selective catalytic reduction over manganese-iron oxides [J]. Chinese Journal of Catalysis, 2014, 35(3): 294-301.

    • 33

      CHIRRANJIT S, SNEHA S, ANIRUDDHA M, et al. Synthesis, characterization of VPO catalyst dispersed on mesoporous silica surface and catalytic activity for cyclohexane oxidation reaction[J]. Microporous and Mesoporous Materials, 2016, 223: 121-128.

    • 34

      GUO X Y, CAL B, WILLIAM H, et al. Effects of sulfate species on V2O5/TiO2 SCR catalysts in coal and biomass-fired systems [J]. Applied Catalysis B: Environmental, 2009, 92(1/2): 30-40.

    • 35

      CHEN J P, YANG R T. Selective catalytic reduction of NO with NH3 on SO42-/TiO2 superacid catalyst[J]. Journal of Catalysis, 1993, 139(1): 277-288.

    • 36

      LU Q, PANG D, ZHANG C, et al. In situ IR studies of Co and Ce doped Mn/TiO2, catalyst for low-temperature selective catalytic reduction of NO with NH3 [J]. Applied Surface Science, 2015, 357(3): 189-196.

    • 37

      NIE J, WU X, MA Z, et al. Tailored temperature window of MnOx -CeO2, SCR catalyst by addition of acidic metal oxides [J]. Chinese Journal of Catalysis, 2014, 35(8): 1281-1288.

    • 38

      CHEN T, GUAN B, LIN H, et al. In situ DRIFTS study of the mechanism of low temperature selective catalytic reduction over manganese-iron oxides [J]. Chinese Journal of Catalysis, 2014, 35(3): 294-301.