Effect of the calcination temperature of cerium–zirconium mixed oxides on the structure and catalytic performance of WO3/CeZrO2 monolithic catalyst for selective catalytic reduction of NOx with NH3

The calcined temperature of the carrier obviously affected SCR activity of catalysts, WO3/Ce0.68Zr0.32O2-500 showed the best low-temperature NH3-SCR activity due to its more Lewis acid sites and stronger redox property.

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NiyCo1-yMn2Ox microspheres for the selective catalytic reduction of NOx with NH3: The synergetic effects between Ni and Co for improving low-temperature catalytic performance

Applied Catalysis A General ◽

10.1016/j.apcata.2018.04.033 ◽

2018 ◽

Vol 560 ◽

pp. 1-11 ◽

Cited By ~ 16

Author(s):

Jian-Wen Shi ◽

Ge Gao ◽

Zhaoyang Fan ◽

Chen Gao ◽

Baorui Wang ◽

...

Keyword(s):

Low Temperature ◽

Selective Catalytic Reduction ◽

Catalytic Reduction ◽

Catalytic Performance ◽

Synergetic Effects ◽

Reduction Of Nox

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Preparation of Mesoporous Mn–Ce–Ti–O Aerogels by a One-Pot Sol–Gel Method for Selective Catalytic Reduction of NO with NH3

Materials ◽

10.3390/ma13020475 ◽

2020 ◽

Vol 13 (2) ◽

pp. 475

Author(s):

Yabin Wei ◽

Shuangling Jin ◽

Rui Zhang ◽

Weifeng Li ◽

Jiangcan Wang ◽

...

Keyword(s):

Selective Catalytic Reduction ◽

Lewis Acid ◽

Catalytic Reduction ◽

Sol Gel ◽

Acid Sites ◽

Lewis Acid Sites ◽

One Pot ◽

Gel Method ◽

Nh3 Scr ◽

Composite Aerogels

Novel Mn–Ce–Ti–O composite aerogels with large mesopore size were prepared via a one-pot sol–gel method by using propylene oxide as a network gel inducer and ethyl acetoacetate as a complexing agent. The effect of calcination temperature (400, 500, 600, and 700 °C) on the NH3–selective catalytic reduction (SCR) performance of the obtained Mn–Ce–Ti–O composite aerogels was investigated. The results show that the Mn–Ce–Ti–O catalyst calcined at 600 °C exhibits the highest NH3–SCR activity and lowest apparent activation energy due to its most abundant Lewis acid sites and best reducibility. The NO conversion of the MCTO-600 catalyst maintains 100% at 200 °C in the presence of 100 ppm SO2, showing the superior resistance to SO2 poisoning as compared with the MnOx–CeO2–TiO2 catalysts reported the literature. This should be mainly attributed to its large mesopore sizes with an average pore size of 32 nm and abundant Lewis acid sites. The former fact facilitates the decomposition of NH4HSO4, and the latter fact reduces vapor pressure of NH3. The NH3–SCR process on the MCTO-600 catalyst follows both the Eley–Rideal (E–R) mechanism and the Langmuir–Hinshelwood (L–H) mechanism.

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Surface structure of crystalline and amorphous chromia catalysts for the selective catalytic reduction of nitric oxide III. Diffuse reflectance ftir study of ammonia desorption from Br�nsted and Lewis acid sites

Journal of Catalysis ◽

10.1016/0021-9517(92)90251-c ◽

1992 ◽

Vol 133 (2) ◽

pp. 431-444 ◽

Cited By ~ 14

Author(s):

M SCHRAMLMARTH

Keyword(s):

Nitric Oxide ◽

Surface Structure ◽

Selective Catalytic Reduction ◽

Lewis Acid ◽

Diffuse Reflectance ◽

Catalytic Reduction ◽

Acid Sites ◽

Lewis Acid Sites ◽

Ammonia Desorption ◽

Reflectance Ftir

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The Enhanced Performance of N-Modified Activated Carbon Promoted with Ce in Selective Catalytic Reduction of NOx with NH3

Catalysts ◽

10.3390/catal10121423 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1423

Author(s):

Marwa Saad ◽

Agnieszka Szymaszek ◽

Anna Białas ◽

Bogdan Samojeden ◽

Monika Motak

Keyword(s):

Catalytic Activity ◽

Activated Carbon ◽

Low Temperature ◽

Selective Catalytic Reduction ◽

Catalytic Reduction ◽

Catalytic Performance ◽

Reduction Mechanism ◽

Modified Activated Carbon ◽

Oxidation Reduction ◽

Reduction Of Nox

The goal of the study was to modify activated carbon (AC) with nitrogen groups and ceria and to test the obtained materials in low temperature selective catalytic reduction of nitrogen oxides. For that purpose, the starting AC was oxidized with HNO3 of various concentrations, modified with urea and doped with 0.5 wt.% of Ce. It was observed that the increased concentration of acid influenced the catalytic activity, since textural and surface chemistry of activated carbon was changed. The most active sample was that modified with 14 M HNO3 and it reached 96% of NO conversion at 300 °C. Additionally, the addition of Ce improved the catalytic performance of modified AC, and NO was reduced according to oxidation–reduction mechanism, characteristic for supported metal oxides. Nevertheless, the samples promoted with Ce emitted significantly higher amount of CO2 comparing to the non-promoted ones.

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Suppression of N2O formation by H2O and SO2 in the selective catalytic reduction of NO with NH3 over a Mn/Ti–Si catalyst

Catalysis Science & Technology ◽

10.1039/c9cy01156k ◽

2019 ◽

Vol 9 (17) ◽

pp. 4759-4770 ◽

Cited By ~ 7

Author(s):

Bolin Zhang ◽

Michael Liebau ◽

Wladimir Suprun ◽

Bo Liu ◽

Shengen Zhang ◽

...

Keyword(s):

Selective Catalytic Reduction ◽

Lewis Acid ◽

No Reduction ◽

Catalytic Reduction ◽

Acid Sites ◽

Lewis Acid Sites ◽

N2o Formation ◽

Brønsted Acid Sites ◽

Reduction Of No ◽

Suppression Effects

Proposed mechanism of NO reduction and N2O formation as well as H2O/SO2 suppression effects with participation of (a) Lewis acid sites and (b) Brønsted acid sites over a Mn/Ti–Si catalyst.

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