Enhanced low-temperature catalytic performance for toluene combustion of CeO2-supported Pt-Ir alloy catalysts

A set of manganese oxide catalysts was synthesized via two preparation techniques: solution combustion synthesis (Mn3O4/Mn2O3-SCS and Mn2O3-SCS) and sol-gel synthesis (Mn2O3-SG550 and Mn2O3-SG650). The physicochemical properties of the catalysts were studied by means of N2-physisorption at −196 °C, X-ray powder diffraction, H2 temperature-programmed reduction (H2-TPR), soot-TPR, X-ray photoelectron spectroscopy (XPS) and field-emission scanning electron microscopy (FESEM). The high catalytic performance of the catalysts was verified in the oxidation of Volatile Organic Compounds (VOC) probe molecules (ethene and propene) and carbon soot in a temperature-programmed oxidation setup. The best catalytic performances in soot abatement were observed for the Mn2O3-SG550 and the Mn3O4/Mn2O3-SCS catalysts. The catalytic activity in VOC total oxidation was effectively correlated to the enhanced low-temperature reducibility of the catalysts and the abundant surface Oα-species. Likewise, low-temperature oxidation of soot in tight contact occurred over the Mn2O3-SG550 catalyst and was attributed to high amounts of surface Oα-species and better surface reducibility. For the soot oxidation in loose contact, the improved catalytic performance of the Mn3O4/Mn2O3-SCS catalyst was attributed to the beneficial effects of both the morphological structure that—like a filter—enhanced the capture of soot particles and to a probable high amount of surface acid-sites, which is characteristic of Mn3O4 catalysts.

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Preparation and Characterization of Bulk and Supported NiB Amorphous Alloy Catalysts with Different Particle Sizes

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.121-123.637 ◽

2007 ◽

Vol 121-123 ◽

pp. 637-640

Author(s):

Lai Jun Wang ◽

Wei Li ◽

M.H. Zhang ◽

K.Y. Tao

Keyword(s):

Amorphous Alloy ◽

Electroless Plating ◽

Chemical Reduction ◽

Reaction System ◽

Catalytic Performance ◽

Ni Catalyst ◽

Particle Sizes ◽

Raney Ni ◽

Reduction Methods ◽

Alloy Catalysts

A series of bulk and supported NiB amorphous alloy catalysts with different particle sizes were prepared by different chemical reduction methods. By adding a certain volume of NH3 to the reaction system and adjusting the reaction temperature, respectively, the velocity of the reaction between Ni2+ and BH4 - could be controlled and the NiB alloys with particle sizes ranging from 10 to 400nm were obtained. A novel method to prepare the supported NiB catalyst, the powder electroless plating method was also studied. The bulk and supported NiB catalysts were characterized by XRD, ICP and TEM. Hydrogenation of sulfolene was selected as the probe reaction to investigate their catalytic performance. The results revealed that the NiB/MgO prepared by Ag inducing electroless plating showed much higher catalytic activity than Raney Ni catalyst, and the powder electroless plating was a promising method to prepare the supported NiB amorphous alloy catalysts.

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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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Synergistic effect of VOx and MnOx surface species for improved performance of V2O5/Ce0.5Ti0.5−xMnxO2−δ catalysts in low-temperature NH3-SCR of NO

Catalysis Science & Technology ◽

10.1039/c8cy02193g ◽

2018 ◽

Vol 8 (24) ◽

pp. 6360-6374 ◽

Cited By ~ 7

Author(s):

Thanh Huyen Vuong ◽

Stephan Bartling ◽

Ursula Bentrup ◽

Henrik Lund ◽

Jabor Rabeah ◽

...

Keyword(s):

Low Temperature ◽

Synergistic Effect ◽

Catalytic Performance ◽

Surface Species ◽

Nh3 Scr ◽

Redox Couples ◽

Scr Of No ◽

Improved Performance

Inserting adjacent Mn3+/Mn2+ and VO3+/VO2+ redox couples in Ce1−xTixO2 improves catalytic performance.

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The Effect of Tourmaline on SCR Denitrification Activity of MnOx/TiO2 at Low Temperature

Catalysts ◽

10.3390/catal10091020 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1020

Author(s):

Yizhe Helian ◽

Suping Cui ◽

Xiaoyu Ma

Keyword(s):

Low Temperature ◽

Catalytic Reduction ◽

Catalytic Performance ◽

Scr Catalyst ◽

Highly Efficient ◽

Nh3 Scr ◽

Catalytic Material ◽

Acidic Sites ◽

Denitrification Activity ◽

The Stability

Selective catalytic reduction (SCR) technology is the most widely used flue gas denitration technology at present. The stability of a catalyst is the main factor limiting the development of this technology. In this study, an environmentally friendly and highly efficient NH3-SCR catalyst was prepared by coprecipitation method from acidolysis residue of industrial waste and tourmaline. We found that the addition of tourmaline has an important impact on the denitration activity of the catalytic material. The NOx conversion exceeded 97% at 200 °C with the dosage of 10% tourmaline, which is about 7% higher than that without doping. The improvement of catalytic performance was mostly attributed to the permanent electrodes of tourmaline, which effectively promotes the dispersion of MnOx/TiO2 catalytic materials, increases the number of acidic sites and changes the valence distribution of manganese ions in products, which speeds up the diffusion of protons and ions, resulting in the acceleration of redox reaction. These as-developed tourmaline-modified MnOx/TiO2 materials have been demonstrated to be promising as a new type of highly efficient low-temperature NH3-SCR catalyst.

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Preparation of Ni/ZrO2/SiO2 Catalyst and its Application in Hydrogenation of CO2 to Methane

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1001.79 ◽

2020 ◽

Vol 1001 ◽

pp. 79-83

Author(s):

Zhen Xing Han ◽

Si Xi Guo ◽

Kai Ming Li ◽

Bing Yao ◽

Ming Song ◽

...

Keyword(s):

Catalytic Activity ◽

Low Temperature ◽

Catalytic Performance ◽

Experimental Results ◽

Impregnation Method ◽

Energy And Environment ◽

Supported Ni ◽

Hydrogenation Of Co

The hydrogenation of CO2 to CH4 can realize the utilization of CO2, which has an important implications to both the energy and environment. As a result of the low catalytic activity of the supported Ni/SiO2 catalyst, the ZrO2 is added to improve its catalytic performance by the impregnation method. The experimental results show that ZrO2 is an effective promoter to enhance the low-temperature catalytic activity of Ni/SiO2 catalyst.

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