Identification of Surface Species on Titania-Supported Manganese, Chromium, and Copper Oxide Low-Temperature SCR Catalysts

2004 ◽  
Vol 108 (28) ◽  
pp. 9927-9936 ◽  
Author(s):  
Donovan A. Peña ◽  
Balu S. Uphade ◽  
Ettireddy P. Reddy ◽  
Panagiotis G. Smirniotis
2015 ◽  
Author(s):  
Padmanabha Reddy Ettireddy ◽  
Adam Kotrba ◽  
Thirupathi Boningari ◽  
Panagiotis Smirniotis

Energies ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 123 ◽  
Author(s):  
Guangli Liu ◽  
Dongtai Han ◽  
Jie Cheng ◽  
Yongshi Feng ◽  
Wenbin Quan ◽  
...  

Hydrocarbons as reductants show promising results for replacing NH3 in SCR technology. Therefore, considerable interest exists for developing low-temperature (<200 °C) and environmentally friendly HC-SCR catalysts. Hence, C2H4 was examined as a reductant using activated-carbon-supported MnOx-based catalyst in low-temperature SCR operation. Its sensitivity to Mn concentration and operating temperature was parametrically studied, the results of which showed that the catalyst activity followed the order of 130 °C > 150 °C > 180 °C with an optimized Mn concentration near 3.0 wt.%. However, rapid deactivation of catalytic activity also occurred when using C2H4 as the reductant. The mechanism of deactivation was explored and is discussed herein in which deactivation is attributed to two factors. The manganese oxide was reduced to Mn3O4 during reaction testing, which contained relatively low activity compared to Mn2O3. Also, increased crystallinity of the reduced manganese and the formation of carbon black occurred during SCR reaction testing, and these constituents on the catalyst’s surface blocked pores and active sites from participating in catalytic activity.


2020 ◽  
Vol 213 ◽  
pp. 01012
Author(s):  
Yufei Zhang

Selective catalytic reduction (SCR) of nitrogen oxides (NOx) using ammonia (NH3) is currently the main technology for flue gas denitration. However, the currently widely used commercial catalysts (such as V2O5-WO3 / TiO2, V2O5-MoO3 / TiO2, etc.) have the disadvantages of high operating temperature, narrow active temperature window, and high catalytic cost. Therefore, in recent years, researchers have devoted themselves to the development of low-cost and efficient low-temperature SCR catalytic materials. This paper summarizes the research progress of low-temperature (less than 250 °C) selective catalytic reduction of NOx by unsupported metal oxide catalysts, supported metal oxide catalysts, precious metals, and molecular sieve catalysts. Among them, manganese-based catalysts show good low-temperature selectivity and stability, and have good application prospects. Finally, the research directions of manganese low temperature SCR catalysts are prospected and theoretically designed based on the existing problems.


2020 ◽  
Vol 267 ◽  
pp. 118668 ◽  
Author(s):  
Shangchao Xiong ◽  
Jianjun Chen ◽  
Nan Huang ◽  
Tao Yan ◽  
Yue Peng ◽  
...  

2013 ◽  
Vol 448-453 ◽  
pp. 885-889
Author(s):  
Xiang Gou ◽  
Kai Zhang ◽  
Lian Sheng Liu ◽  
Wen Yong Liu ◽  
Zi Fang Wang ◽  
...  

The method of selective catalytic reduction (SCR) to removal NOx is very mature. However, its initial investment and operation cost are still high, which limits the development of SCR technology. Low temperature SCR catalysts can significantly reduce the cost. Catalyst active component and its carrier is the key to the efficiency of denitration. This paper summarizes the research progress of noble metal catalyst of low temperature SCR.


Catalysts ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 135 ◽  
Author(s):  
Tao Zhu ◽  
Xing Zhang ◽  
Wenjing Bian ◽  
Yiwei Han ◽  
Tongshen Liu ◽  
...  

With the improvement of environmental protection standards, selective catalytic reduction (SCR) has become the mainstream technology of flue gas deNOx. Especially, the low-temperature SCR nano-catalyst has attracted more and more attention at home and abroad because of its potential performance and economy in industrial applications. In this paper, low-temperature SCR catalysts were prepared using the activated carbon loading MnOx-Cu. Then, the catalysts were packed into the fiedbed stainless steel micro-reactor to evaluate the selective catalytic reduction of NO performance. The influence of reaction conditions was investigated on the catalytic reaction, including the MnOx-Cu loading amount, calcination and reaction temperature, etc. The experimental results indicate that SCR catalysts show the highest catalytic activity for NO conversion when the calcination temperature is 350 °C, MnOx loading amount is 5%, Cu loading amount is 3%, and reaction temperature is 200 °C. Under such conditions, the NO conversion arrives at 96.82% and the selectivity to N2 is almost 99%. It is of great significance to investigate the influence of reaction conditions in order to provide references for industrial application.


Alloy Digest ◽  
1965 ◽  
Vol 14 (1) ◽  

Abstract Jessair is a manganese, chromium, molybdenum alloy steel combining the deep harding characteristics of air-hardening steels with the simplicity of low temperature heat treatment possible in many oil-hardening steels. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and bend strength as well as fracture toughness and fatigue. It also includes information on forming, heat treating, machining, and joining. Filing Code: TS-157. Producer or source: Jessop Steel Company.


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