Selective Catalytic Reduction of NOx on VCuMn/TiO2 at Middle-Low Temperature

2012 ◽  
Vol 550-553 ◽  
pp. 128-131
Author(s):  
Zhi Hang Chen ◽  
Zhi Xiong Tang ◽  
Chao Ping Cen ◽  
Huan Mu Zeng ◽  
Ding Sheng Chen ◽  
...  
Keyword(s):  
Low Temperature ◽  
Catalytic Reduction ◽  
Space Velocity ◽  
Impregnation Method ◽  
X Ray Diffraction ◽  
Sulfur Resistance ◽  
X Ray ◽  
High Sulfur Content ◽  
Scr Of No ◽  
Low Temperature Scr

In this dissertation, combinatorial chemistry was adopted, and the activities of a series of VCuMn/TiO2catalysts prepared by impregnation method for middle-low temperature SCR of NOxwere evaluated. The activity datas showed that 2V2Cu8Mn/TiO2exhibited better activity. At 200 °C, above 70% NOxconversion were both obtained with a gas hourly space velocity of 60,000 h-1, and NOxconversion of 2V2Cu8Mn/TiO2reached nearly 100% at 275~325 °C. The X-ray diffraction characterization showed that the CuO and Mn2O3phases in VCuMn/TiO2catalysts were the main active site and with better SCR activity at middle-low temperature. In addition, sulfur-resistance of VCuMn/TiO2catalysts were investigated, NOxconversion on 2V2Cu8Mn/TiO2was above 60% at 250 °C after feeding SO2(600 ppm). It can be concluded that the modified VCu/TiO2catalyst by adding manganese obtained a good de-NOxactivity in a high sulfur content gas stream.

scholarly journals Nanosized V-Ce Oxides Supported on TiO2 as a Superior Catalyst for the Selective Catalytic Reduction of NO

Catalysts ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 202
Author(s):  
Long Lu ◽  
Xueman Wang ◽  
Chunhua Hu ◽  
Ying Liu ◽  
Xiongbo Chen ◽  
...  
Keyword(s):  
Low Temperature ◽  
Selective Catalytic Reduction ◽  
Photoelectron Spectroscopy ◽  
Catalytic Reduction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Redox Capacity ◽  
Scr Of No ◽  
Temperature Programmed

Nanosized V-Ce oxides supported on TiO2 (VCT) were prepared and utilized in the low-temperature selective catalytic reduction (SCR) of NO with NH3. Compared with the other V-Ce oxides-based catalysts supported on Al2O3, ZrO2, and ZSM-5, VCT showed the best SCR activity in a low-temperature range. The NOx conversion of 90% could be achieved at 220 °C. Characterizations including X-ray diffraction (XRD), scanning election micrograph (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), temperature-programmed desorption with NH3 (NH3-TPD), and temperature-programmed reduction with H2 (H2-TPR) showed that V1.05Ce1/TiO2 exhibited a good dispersion of V2O5, enrichment of surface Ce3+ and chemical-absorbed oxygen, and excellent redox capacity and acidity, which resulted in the best SCR performance at low temperature.

Studies on the Preparation and DeNOx Performance of MnxOy/CNTs Catalyst for Low-Temperature Selective Catalytic Reduction

2013 ◽  
Vol 798-799 ◽  
pp. 231-234 ◽  
Author(s):  
Bing Nan Ren ◽  
Qiao Wen Yang
Keyword(s):  
Low Temperature ◽  
Selective Catalytic Reduction ◽  
Oxide Catalyst ◽  
Catalytic Reduction ◽  
Space Velocity ◽  
Impregnation Method ◽  
Active Components ◽  
Reaction Conditions ◽  
No Conversion ◽  
Scr Of No

The metal oxide catalyst was prepared by loading MnxOyon carbon nanotubes (CNTs) with impregnation method. Then the catalyst was characterized by BET, TEM and XPS, and the catalytic activity of the catalyst for selective catalytic reduction (SCR) of NO at low-temperature was investigated. The results showed that the species of active components loaded on the catalyst were MnO2and Mn2O3. The NO conversion was improved with reduction temperature increase under 250°C, increased slowly over 250°C. The O2content had an outstanding effect on NO conversion of catalysts at a low concentration range. Once the oxygen content was enhanced over 5%, there was no significant increase in the NO conversion. With the increasing of space velocity, the NO conversion rate was decreased under the reaction conditions.

Research of SO2 Resistance of MnOx Catalyst Modified by Ce for Low Temperature SCR with NH3

2011 ◽  
Vol 356-360 ◽  
pp. 529-532 ◽  
Author(s):  
Yan Wang ◽  
Liu Yang ◽  
Wei Ping Liao ◽  
Fei Wang
Keyword(s):  
Low Temperature ◽  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Area Measurement ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermal Gravimetry ◽  
Surface Area Measurement ◽  
Low Temperature Scr

Two catalysts, MnOx and ceria modified MnOx were prepared by deposition-precipitation method and used for low-temperature selective catalytic reduction (SCR) with NH3in the presence of SO2. The catalysts were characterized by X-ray diffraction (XRD), surface area measurement (BET) and thermal gravimetry analysis(TG). The deactivation of MnOx and MnOx-CeO2by SO2was observed during SCR process. It was found that the resistance to SO2could be greatly enhanced for Ce modified MnOx. It was because that the formation of Mn(SO4)x was prevented and the depositions of (NH4)2SO4and NH4HSO4were significantly inhibited with the doping of ceria.

Experimental Study on Preparation and Operating Conditions over a Promising Monolithic Catalysts for NOx Removal: MnOx/TiO2/Cordierite

2017 ◽  
Vol 898 ◽  
pp. 1905-1915 ◽  
Author(s):  
Kai Qi ◽  
Jun Lin Xie ◽  
Feng Xiang Li ◽  
Feng He
Keyword(s):  
Low Temperature ◽  
Catalytic Reduction ◽  
Sol Gel ◽  
Operating Conditions ◽  
Molar Ratio ◽  
Impregnation Method ◽  
Scope Of Application ◽  
Catalyst Dosage ◽  
Cordierite Honeycomb ◽  
Low Temperature Scr

The samples of MnOx/TiO2 catalysts supported on cordierite honeycomb ceramics were prepared by a sol-gel-impregnation method, and evaluated for low-temperature (353-473 K) selective catalytic reduction (SCR) of NOx with NH3. The influences of pretreatment on cordierite and catalyst dosage were investigated at first and optimized as follows: pickling for cordierite honeycomb ceramics with 1 mol/L HNO3 for 3 h prior to loading procedure as well as the catalyst dosage of 3-5 wt.%. The activity results indicated that there was an optimum working condition for MnOx/TiO2/cordierite catalysts: NH3/NO molar ratio=1.1, [O2]=3 vol.%, GHSV=5514 h-1, the highest activity of nearly 100% NO conversion could be obtained. As a comparison, the performances of commercialized vanadium-based honeycomb catalyst were also employed, which revealed the narrower scope of application of GHSV and the higher active temperature window. In conclusion, it turns out that the prepared MnOx/TiO2/cordierite catalysts are more applicable as a low-temperature SCR catalyst for NOx removal in a more complicated application environment.

scholarly journals Mechanism and Performance of the SCR of NO with NH3 over Sulfated Sintered Ore Catalyst

Catalysts ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 90 ◽  
Author(s):  
Wangsheng Chen ◽  
Fali Hu ◽  
Linbo Qin ◽  
Jun Han ◽  
Bo Zhao ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Catalytic Reduction ◽  
Nox Reduction ◽  
Space Velocity ◽  
Acid Sites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffuse Reflectance Infrared Spectroscopy ◽  
And Performance ◽  
Diffuse Reflectance Infrared

A sulfated sintered ore catalyst (SSOC) was prepared to improve the denitration performance of the sintered ore catalyst (SOC). The catalysts were characterized by X-ray Fluorescence Spectrometry (XRF), Brunauer–Emmett–Teller (BET) analyzer, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance infrared spectroscopy (DRIFTS) to understand the NH3-selective catalytic reduction (SCR) reaction mechanism. Moreover, the denitration performance and stability of SSOC were also investigated. The experimental results indicated that there were more Brønsted acid sites at the surface of SSOC after the treatment by sulfuric acid, which lead to the enhancement of the adsorption capacity of NH3 and NO. Meanwhile, Lewis acid sites were also observed at the SSOC surface. The reaction between −NH2, NH 4 + and NO (E-R mechanism) and the reaction of the coordinated ammonia with the adsorbed NO2 (L-H mechanism) were attributed to NOx reduction. The maximum denitration efficiency over the SSOC, which was about 92%, occurred at 300 °C, with a 1.0 NH3/NO ratio, and 5000 h−1 gas hourly space velocity (GHSV).

scholarly journals Selective Catalytic Reduction of NO with NH3 over Ce-W-Ti Oxide Catalysts Prepared by Solvent Combustion Method

2018 ◽  
Vol 8 (12) ◽  
pp. 2430 ◽  
Author(s):  
Xinbo Zhu ◽  
Yaolin Wang ◽  
Yu Huang ◽  
Yuxiang Cai
Keyword(s):  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Space Velocity ◽  
Combustion Method ◽  
Catalytic Performance ◽  
Solution Combustion ◽  
X Ray ◽  
Nh3 Scr ◽  
Scr Of No ◽  
Temperature Programmed

In this work, a series of Ce-W-Ti catalysts were synthesized using a solution combustion method for the selective catalytic reduction (SCR) of NO with NH3 at low temperatures. The reaction performance of NH3-SCR of NO was significantly improved over the Ce-W-Ti catalysts compared to Ce0.4Ti and W0.4Ti catalysts, while Ce0.2W0.2Ti showed the best activity among all the samples. The Ce0.2W0.2Ti catalyst exhibited over 90% removal of NO and 100% N2 selectivity in the temperature range of 250–400 °C at a gas hourly space velocity (GHSV) of 120,000 mL·g−1·h−1. The Ce-W-Ti catalysts were characterized using N2 adsorption-desorption, X-ray diffraction, X-ray photoelectron spectrometry and temperature programmed desorption of NH3 to establish the structure-activity relationships of the Ce-W-Ti catalysts. The excellent catalytic performance of the Ce0.2W0.2Ti catalyst could be associated with the larger specific surface area, highly dispersed Ce and W species, increased amount of surface adsorbed oxygen (Oads) and enhanced total acidity on the catalyst surfaces.

The Effect of Doping Ce and Fe on the Mn/TiO2 Catalyst for Low Temperature NO Selective Catalytic Reduction with NH3

2012 ◽  
Vol 260-261 ◽  
pp. 1041-1046 ◽  
Author(s):  
Shi Ye Feng ◽  
Pan Gao ◽  
Chang Qing Dong ◽  
Qiang Lu
Keyword(s):  
Iron Oxide ◽  
Low Temperature ◽  
Titanium Oxide ◽  
Catalytic Reduction ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Reduction Of No ◽  
X Ray ◽  
Cerium Oxides ◽  
Oxide Support

A series of manganese-cerium oxide support titanium oxide with different Fe/Ti, Ce/Ti ratio were investigated for selectivity catalytic reduction of NO low at temperature with NH3 as a reducing agent. The catalysts base Mn/TiO2were prepared by sol-gel. The effect of amount of Ce and Fe oxide on the NO conversion of Mn/TiO22was studied. X-ray diffraction (XRD), temperature program desorption (TPD) were carried out. It was known that cerium oxides and iron oxide promoted preformance of Mn/TiO2 for low temperature. because Lewis is mainly take important role in the reaction for low temperature.

Effect of the Addition of In to Co/HMCM-49 Catalyst for the Selective Catalytic Reduction of NO Under Lean-burn Conditions

2010 ◽  
Vol 224 (06) ◽  
pp. 907-920 ◽  
Author(s):  
Fei Li ◽  
Dehai Xiao ◽  
Jing Li ◽  
Xiangguang Yang
Keyword(s):  
Selective Catalytic Reduction ◽  
Wide Temperature Range ◽  
Catalytic Reduction ◽  
Temperature Programmed Desorption ◽  
X Ray Diffraction ◽  
Lean Burn ◽  
Reduction Of No ◽  
X Ray ◽  
Scr Of No ◽  
Temperature Programmed

AbstractSelective catalytic reduction (SCR) of NO with propane using bimetals (3Co2Ce, 3Co2Sr, 3Co2Sn and 3Co2In) loaded on HMCM-49 zeolite was studied under lean-burn condition. Only 3Co2In/HMCM-49 exhibited higher deNOx activity in a wide temperature range. The catalysts were characterized by N2-adsoption, X-ray diffraction (XRD), temperature-programmed surface reactions (TPSR) and temperature-programmed desorption (TPD) of NO. TPSR and TPD results exhibited that the addition of In inhibited the oxidation ability of Co on 3Co2In/HMCM-49 catalyst, but enhanced NOx adsorption.

The Study of the MnOx/TiO2-ZrO2 Used in the Sintering Flue Gas Low-Temperature Selective Catalytic Reaction

2013 ◽  
Vol 641-642 ◽  
pp. 551-556 ◽  
Author(s):  
Xi Ning Lu ◽  
Cun Yi Song
Keyword(s):  
Low Temperature ◽  
Manganese Oxides ◽  
Catalytic Reduction ◽  
Sol Gel ◽  
Surface Concentration ◽  
Space Velocity ◽  
X Ray Diffraction ◽  
Active Point ◽  
Reduction Of Nox ◽  
High Space

TiO2, 50%TiO2-ZrO2 and 80%TiO2-ZrO2 were prepared by sol-gel method. The manganese oxides were impregnated on the carrier and the catalysts were used for low-temperature selective catalytic reduction of NOx with ammonia (NH3-SCR) in the presence of excess O2. The samples were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The results showed that the particle size of 80%TiO2-ZrO2 is the smallest among the three kind of carrier and the particles are highly dispersed. By adding the ZrO2, the Zr4+ ions replaced the lattice Ti4+ ions, and thus caused lattice distortion in the TiO2 and an increase of the active point amount on the carrier. Furthermore, the Zr also promoted the dispersion of the active ingredients carried on the carrier, increased the surface concentration of Mn. The most active catalyst was obtained with a mass MnOx/80%TiO2-ZrO2 ratio of 0.1.The best MnOx/80%TiO2-ZrO2 catalyst yielded nearly 92.6% NO conversion at 130°C at a high space velocity of 67,000 h-1.

Denitrification Activities of Mg-Mo-V-Ti Catalysts Prepared by Dipping Method at Low Temperature

2018 ◽  
Vol 913 ◽  
pp. 893-899
Author(s):  
Dong Zhu Ma ◽  
Jian Li ◽  
Ling Zhang ◽  
Peng Guo ◽  
Zi Qiang Wen ◽  
...  
Keyword(s):  
Low Temperature ◽  
Selective Catalytic Reduction ◽  
Oxygen Content ◽  
Oxygen Concentration ◽  
Flue Gas ◽  
Catalytic Reduction ◽  
Fixed Bed ◽  
Space Velocity ◽  
Fixed Bed Reactor ◽  
Sulfur Resistance

Mg-Mo-V-Ti catalysts of low temperature denitrification were prepared by dipping method. In order to study the activity of selective catalytic reduction, the catalyst was placed in a fixed bed reactor. Industrial flue gas was simulated with cylinder gas. Results indicate that the 0.1wt% content of MgO catalyst has good performance on denitration activity and sulfur resistance. The effects of oxygen content, space velocity and reaction temperature on the activity of the 0.1MgO-6MoO3-3V2O5-TiO2 wt% catalyst were investigated. With the increase of oxygen concentration, the denitrification efficiency increases when the oxygen concentration is less than 8%. When the oxygen content is greater than 8%, the denitrification efficiency is almost the same. The denitrification efficiency decreases with the increase of space velocity. The removal efficiency of NO 0.1MgO-6MoO3-3V2O5-TiO2 wt% catalyst over increases first and then becomes stable with the increase of temperature, and the conversion efficiency of SO2 is less than or equal to 2.2% at 120~240 °C.

Sign in / Sign up

Export Citation Format

Share Document