Mechanism of propene poisoning on Cu-SSZ-13 catalysts for SCR of NOx with NH3

Ma, Lei; Su, Wenkang; Li, Zhenguo; Li, Junhua; Fu, Lixin; Hao, Jiming

doi:10.1016/j.cattod.2014.05.027

Cited by 54 publications

(45 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, the competitive adsorption between C 3 H 6 and NO x would inhibit the NH 3 -SCR performance of Cu catalyst which has been confirmed by Ma et al 19 In contrast, the addition of C 3 H 6 did not significantly affect the NH 3 -SCR activity of Cu catalyst at temperatures above 400 °C. The HC-SCR activity of the Cu catalyst was also tested, and the results were shown in Fig.…”

Section: Oxidation Performance Of Cu Andmentioning

confidence: 54%

“…Heo et al 13 reported that the competitive adsorption between C 3 H 6 and NH 3 on the surface of the catalysts and the useless consumption of NH 3 by side reaction caused the inhibition of the NH 3 -SCR activity of Cu-ZSM5, and the extent of inhibition effect aggravated with the concentration of C 3 H 6 increasing. Moreover, for the CHA-based catalyst, Ma et al 19 found that the competitive adsorption process between NO x and C 3 H 6 as well as coke deposition on the surface of the catalyst contributed to the deactivation of Cu-CHA catalyst. Moreover, for the CHA-based catalyst, Ma et al 19 found that the competitive adsorption process between NO x and C 3 H 6 as well as coke deposition on the surface of the catalyst contributed to the deactivation of Cu-CHA catalyst.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Cerium promotion on the hydrocarbon resistance of a Cu-SAPO-34 NH₃-SCR monolith catalyst

Cao

Feng

et al. 2015

Catal. Sci. Technol.

View full text Add to dashboard Cite

CuCe-SAPO-34 (CuCe-x) catalysts with 3 wt% Cu and various contents of Ce for selective catalytic reduction of NO x by NH 3 (NH 3 -SCR) were prepared by wet co-impregnation method. The activities of CuCe-x catalysts were better than that of Cu-SAPO-34 (Cu). In addition, hydrocarbons (HCs) resistance of the CuCe-x catalysts was examined and compared to that of Cu catalyst. The NH 3 -SCR performance after UV-vis-DRS and H 2 -TPR results confirmed that the addition of Ce could inhibit the aggregation of CuO crystallites and increase the amount of isolated copper ions. Furthermore, the NH 3 -TPD and TGA results demonstrated that the addition of Ce decreased the amount and strength of strong acid sites, so that the amounts of C 3 H 6 /O 2 adsorption on CuCe-x catalysts were lower than that on Cu catalyst. Therefore, activity and HCs resistance of Cu-SAPO-34 was improved by the addition of Ce.

show abstract

Section: Oxidation Performance Of Cu Andmentioning

confidence: 54%

mentioning

confidence: 99%

Cerium promotion on the hydrocarbon resistance of a Cu-SAPO-34 NH₃-SCR monolith catalyst

Cao

Feng

et al. 2015

Catal. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…Its oxidation is more pronounced in the presence of C3H6, compared to the carbon-free conditions, suggesting once again a promoting effect for the formation of free radicals. This is supported by literature, where oxidation of propene to acrolein on Cu-SSZ-13 has been observed with DRIFTS at 350 °C and ambient pressure [21] and even gas phase oxidation to e.g. propene oxide is known at higher pressure [39].…”

Section: Effect Of Propene On Scr-activitymentioning

confidence: 55%

“…1). Hence, the possible adsorbed species at low temperatures (after C3H6 dosage step) have no influence on the SCR-activity as they are most probably easily replaced by NOx [21]. A direct comparison of the Standard-SCR-activity with and without dosing C3H6 (Fig.…”

Section: Effect Of Propene On Scr-activitymentioning

confidence: 99%

“…Also unburned hydrocarbons lead to a more pronounced poisoning effect on medium-pore sized Cu-ZSM-5 compared to the small-pore sized Cu-SSZ-13 [19]. In all cases, the entering hydrocarbons may adsorb in competition with NH3 and NOx, and therefore hinder the SCR-reaction [20,21]. This adsorption does not only occur on the acidic sites but also on the catalytically active Cu-sites [22] and shows a dependency on the concentration and type of hydrocarbons [23].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Cu-SSZ-13 as pre-turbine NOx-removal-catalyst: Impact of pressure and catalyst poisons

Günter

Pesek

Schäfer

et al. 2016

Applied Catalysis B: Environmental

View full text Add to dashboard Cite

Fully Copper‐Exchanged High‐Silica LTA Zeolites as Unrivaled Hydrothermally Stable NH₃‐SCR Catalysts

et al. 2017

View full text Add to dashboard Cite

Tighter CO2 emission standards from mobile sources are being legislated globally in order to address the concerns regarding anthropogenic climate change. Hence, automotive manufacturers have developed a variety of new propulsion systems, including battery electric, plug-in hybrid, and even fuel cell electric vehicles.[1] However, there is a general consensus that internal combustion engines will continue to dominate the market for the foreseeable future. [1,2] As such, fuel-efficient combustion technologies like diesel engines offer superior green-house gas reduction potential. One technical obstacle to broader diesel implementation is the required lean NOx aftertreatment system, especially to meet upcoming strict emission regulations. NOx is extremely difficult to reduce under an oxygen-rich environment.[3] Although its selective catalytic reduction by urea (urea-SCR) has recently been commercialized, the operation window of this technology is severely limited by the decomposition temperature (~ 200 °C) of urea into NH3 and by SCR catalyst deactivation at temperatures higher than 750 °C.[4]This prohibits closer placement of the catalyst to the engine, requiring an aggressive warm-up with extra fuel burning during the cold-start. Furthermore, when integrating a mandatory particulate filter in the modern diesel aftertreatment system to mitigate soot and ash, the frequent regeneration of diesel particulate filters is required before a certain accumulation of soot, resulting in large temperature spikes. Improvement of the thermal durability of the SCR catalysts would, therefore, be the key to maximizing the fuel efficiency, as well as to producing clean emissions from diesel engines. Metal-exchanged zeolites have drawn much attention as diesel vehicle SCR catalysts, and with copper-exchanged ZSM-5 and SSZ-13, which are medium-and small-pore zeolites with MFI and CHA topologies, respectively, [5] have been most widely studied for this reaction.[4] Cu-SSZ-13 has recently been implemented as the current standard catalyst in the mobile SCR technology because of its superior thermal durability compared to already known catalysts. When aged at 850 °C, however, even this catalyst, whose fresh form achieves greater than 90% NOx conversion at 250 -400 °C in steady state, loses its CHA structure and forms copper oxide (CuOx) species, leading to severe activity loss. [6] Although zeolite A (framework type LTA) is the first synthetic zeolite to be prepared, [7] its catalytic applications have long been severely restricted due to its poor thermal stability originating from the high framework Al content (Si/Al = 1.0). However, a recent success in the benzylimidazolium-mediated synthesis of its unprecedented high-silica (Si/Al > 8) form provides a key advantage in terms of structural stability with tunable loading of catalytically-active metal centers.[8] Here we report that when the copper ion exchange level increases to 100% (Cu/Al = 0.50), the high-silica (Si/Al = 16-23) Cu-LTA catalysts hydrothermally aged at 900 °C, i.e., t...

show abstract

Mechanism of propene poisoning on Cu-SSZ-13 catalysts for SCR of NOx with NH3

Cited by 54 publications

References 46 publications

Cerium promotion on the hydrocarbon resistance of a Cu-SAPO-34 NH₃-SCR monolith catalyst

Cerium promotion on the hydrocarbon resistance of a Cu-SAPO-34 NH₃-SCR monolith catalyst

Cu-SSZ-13 as pre-turbine NOx-removal-catalyst: Impact of pressure and catalyst poisons

Fully Copper‐Exchanged High‐Silica LTA Zeolites as Unrivaled Hydrothermally Stable NH₃‐SCR Catalysts

Contact Info

Product

Resources

About

Mechanism of propene poisoning on Cu-SSZ-13 catalysts for SCR of NOx with NH3

Cited by 54 publications

References 46 publications

Cerium promotion on the hydrocarbon resistance of a Cu-SAPO-34 NH3-SCR monolith catalyst

Cerium promotion on the hydrocarbon resistance of a Cu-SAPO-34 NH3-SCR monolith catalyst

Cu-SSZ-13 as pre-turbine NOx-removal-catalyst: Impact of pressure and catalyst poisons

Fully Copper‐Exchanged High‐Silica LTA Zeolites as Unrivaled Hydrothermally Stable NH3‐SCR Catalysts

Contact Info

Product

Resources

About

Cerium promotion on the hydrocarbon resistance of a Cu-SAPO-34 NH₃-SCR monolith catalyst

Cerium promotion on the hydrocarbon resistance of a Cu-SAPO-34 NH₃-SCR monolith catalyst

Fully Copper‐Exchanged High‐Silica LTA Zeolites as Unrivaled Hydrothermally Stable NH₃‐SCR Catalysts