Review of Catalysts for Selective Catalytic Reduction (SCR) of NOx

2012 ◽  
Vol 550-553 ◽  
pp. 119-123 ◽  
Author(s):  
Hong Dan Xue ◽  
Guo Li Li ◽  
Pu Liu ◽  
Fu Li Wang ◽  
Yong Qing Bai ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Catalytic Activity ◽  
Metal Oxides ◽  
Selective Catalytic Reduction ◽  
Noble Metals ◽  
Catalytic Reduction ◽  
Composite Type ◽  
Scr Of No ◽  
And Storage

This paper reviews various catalysts for removal of NOx in SCR,including noble metals,zeolites,metal oxides and so on.These traditional catalysts do not have excellent properties in all aspects such as catalytic activity, thermal stability and resistance against poisoning,so they can hardly be commercialized.However,composite type catalysts and storage-reduction catalyst for removal NOx overcome the above disadvantages of traditional catalysts and have promising prospects.

Effect of Cerium on Manganese Base Catalysts by Co-Precipitation for Low-Temperature SCR of NO with NH3

2014 ◽  
Vol 633 ◽  
pp. 121-124 ◽  
Author(s):  
Liang Jing Zhang ◽  
Su Ping Cui ◽  
Hong Xia Guo ◽  
Xiao Yu Ma ◽  
Xiao Gen Luo
Keyword(s):  
Catalytic Activity ◽  
Low Temperature ◽  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Precipitation Method ◽  
Base Catalysts ◽  
Nox Conversion ◽  
Scr Of No ◽  
Co Precipitation ◽  
Low Temperature Scr

Catalysts of Mn/TiO2 and Mn-Ce /TiO2 prepared by co-precipitation method for low temperature selective catalytic reduction (SCR) of NO with NH3 were investigated in this study. The experimental results showed that co-precipitation method after improvement, the NO conversion of Mn-Ce/TiO2 catalyst increased sharply. Meanwhile, the addition of cerium has significant effects on the catalytic activity. Characterizations of catalysts were carried out by XRD, BET and H2-TPR. The characterized results indicated that co-precipitation method after improvement, in temperature windows 150 to 300 °C, showed higher NOx conversion.

Low-Temperature Selective Catalytic Reduction of NO with NH3 Over Mn-Fe Mixed Metal Oxides on the Nitric Vapor Functionalized Carbon Nanotubes Prepared by a Polyol Process

NANO ◽  
2017 ◽  
Vol 12 (04) ◽  
pp. 1750048
Author(s):  
Xin Lv ◽  
Liheng Zhang ◽  
Sheng Zhan ◽  
Zhen Li ◽  
Yi Zeng
Keyword(s):  
Carbon Nanotubes ◽  
Low Temperature ◽  
Metal Oxides ◽  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Polyol Process ◽  
Mixed Metal Oxides ◽  
Functionalized Carbon Nanotubes ◽  
X Ray ◽  
Scr Of No

Highly dispersed Mn-Fe mixed metal oxides were supported on the nitric vapor functionalized carbon nanotubes (CNTs) by the polyol process for the low-temperature selective catalytic reduction (SCR) of NO with NH3. X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), H2 temperature-programmed reduction (H2-TPR) and Fourier transform infrared (FT-IR) spectroscopy have been used to elucidate the structure and surface properties of the obtained catalysts. It was found that the Mn-Fe/VF-CNTs catalysts synthesized by the polyol process exhibited higher activity and more extensive operating-temperature window, compared to the catalysts prepared by the impregnation method. On the basis of the catalyst characterization, the better dispersion of metal oxides on the CNTs surface, the more chemisorbed oxygen species, the higher Mn[Formula: see text]/Mn and O[Formula: see text]/O[Formula: see text]O[Formula: see text] ratios played key roles in the excellent catalytic performance of the catalyst in the low-temperature SCR of NO to N2 with NH3.

Modification of Nano Spherical-Like MnOx/TiO2 Catalysts with F-Doped

2017 ◽  
Vol 898 ◽  
pp. 1896-1904
Author(s):  
Jun Lin Xie ◽  
Feng Xiang Li ◽  
Hai Feng Cui ◽  
Feng He ◽  
Kai Qi
Keyword(s):  
Catalytic Activity ◽  
Low Temperature ◽  
Selective Catalytic Reduction ◽  
Spherical Particle ◽  
Surface Area ◽  
Catalytic Reduction ◽  
Sol Gel ◽  
Acid Sites ◽  
Scr Of No ◽  
Structures And Properties

A series of spherical-like MnOx/TiO2 catalysts with F-doped were prepared by using sol-gel method and investigated for low-temperature selective catalytic reduction (SCR) of NOx with NH3 at the temperature ranging from 100 °C to 200 °C. The 0.07Ce-MnOx/TiO2 catalyst shows the highest activity and yields 95% NO conversion at 200 °C. With the help of XRD, TGA, H2-TPR, NH3-TPD, BET and TEM, the structures and properties of the catalysts were characterized. The results show that it is a fine modifier for TiO2 support with appropriate amounts of F doping, and F ions can enter into TiO2 lattice, reducing the formation of rutile TiO2 and the crystallization of MnOx. However, MnTiO3 was generated in the catalysts with excess F doping. This would cause larger diameter of spherical particle and smaller surface area. But the amounts of the surface acid sites increased, and the reduction ability of catalysts was enhanced, which is beneficial for catalytic activity of the catalysts.

Effect of Calcinations Temperature of Cu/Ti-PILCs for Selective Catalytic Reduction of NO by Propylene

2011 ◽  
Vol 396-398 ◽  
pp. 776-781
Author(s):  
Qi Ying Wang ◽  
Zi Li Liu ◽  
Han Bo Zou ◽  
Zhao Hui Zhao ◽  
Zhao Qing Liu ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Catalytic Activity ◽  
Pore Structure ◽  
Selective Catalytic Reduction ◽  
Active Component ◽  
Catalytic Reduction ◽  
Active Species ◽  
Reduction Of No ◽  
Good Thermal Stability ◽  
Highly Dispersed

Catalyst Cu/Ti-PILCs were used for selective catalytic reduction of NO by propylene. The effect of calcinations temperature of Cu/PILCs on catalytic activity, pore structure and active species were investigated. Cu/Ti-PILCs calcined at 500°C had best activity. On 500°C-calcined catalyst, the Cu species was highly-dispersed and existed mainly as Cu2＋species which was the catalytic active component to SCR reaction. The pore structure of Cu/Ti-PILCs had good thermal stability below 600°C calcinations. 700°C-calcined catalyst has poor catalytic activity. High-temperature calcinations destroyed the catalyst’s pore structure, and formed CuO bulky aggregation which had no catalytic activity, all these led to the decrease of the SBET of catalysts and the drop of catalytic activity.

Synthesis of high-silica AEI zeolites with enhanced thermal stability by hydrothermal conversion of FAU zeolites, and their activity in the selective catalytic reduction of NOx with NH3

2015 ◽  
Vol 3 (2) ◽  
pp. 857-865 ◽  
Author(s):  
Takushi Sonoda ◽  
Toshihiro Maruo ◽  
Yoshitaka Yamasaki ◽  
Nao Tsunoji ◽  
Yasuyuki Takamitsu ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Catalytic Performance ◽  
Hydrothermal Conversion ◽  
Scr Of No ◽  
High Silica ◽  
Reduction Of Nox

Cu-loaded AEI catalysts with different P/Al ratios showed a good catalytic performance for NH3-SCR of NOx.

The synergistic effects between Ce and Cu in CuyCe1−yW5Ox catalysts for enhanced NH3-SCR of NOx and SO2 tolerance

2019 ◽  
Vol 9 (3) ◽  
pp. 718-730 ◽  
Author(s):  
Jian-Wen Shi ◽  
Yao Wang ◽  
Ruibin Duan ◽  
Chen Gao ◽  
Baorui Wang ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Selective Catalytic Reduction ◽  
Low Temperatures ◽  
Catalytic Reduction ◽  
Synergistic Effects ◽  
Reduction Of No ◽  
Nh3 Scr ◽  
So2 Tolerance ◽  
Scr Of Nox

Non-manganese-based metal oxides are promising catalysts for the NH3-SCR (selective catalytic reduction) of NOx at low temperatures.

scholarly journals Novel Preparation of Cu and Fe Zirconia Supported Catalysts for Selective Catalytic Reduction of NO with NH3

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 55
Author(s):  
Katarzyna Świrk ◽  
Ye Wang ◽  
Changwei Hu ◽  
Li Li ◽  
Patrick Da Costa ◽  
...  
Keyword(s):  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Supported Catalysts ◽  
Catalytic Performance ◽  
Experimental Conditions ◽  
One Pot ◽  
Nh3 Scr ◽  
Scr Of No ◽  
Temperature Programmed ◽  
Stationary Sources

Copper and iron promoted ZrO2 catalysts were prepared by one-pot synthesis using urea. The studied catalysts were characterized by XRD, N2 physisorption, XPS, temperature-programmed desorption of NH3 (NH3-TPD), and tested by the selective catalytic reduction by ammonia (NH3-SCR) of NO in the absence and presence of water vapor, under the experimental conditions representative of exhaust gases from stationary sources. The influence of SO2 on catalytic performance was also investigated. Among the studied catalysts, the Fe-Zr sample showed the most promising results in NH3-SCR, being active and highly selective to N2. The addition of SO2 markedly improved NO and NH3 conversions during NH3-SCR in the presence of H2O. The improvement in acidic surface properties is believed to be the cause.

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