Effective catalysts for the low-temperature NH3-SCR process based on MCM-41 modified with copper by template ion-exchange (TIE) method

Kowalczyk, Andrzej; Święs, Aneta; Gil, Barbara; Rutkowska, Małgorzata; Piwowarska, Zofia; Borcuch, Aleksandra; Michalík, Marek; Chmielarz, Lucjan

doi:10.1016/j.apcatb.2018.06.052

Cited by 45 publications

(52 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Deposition of copper by the ion-exchange method resulted possibly in the preferential location of copper cations in ion-exchange positions; however, deposition of copper on the amorphous silica surface cannot also be excluded. Our previous studies for MCM-41 modified with copper showed its relatively high catalytic activity in the NH 3 -SCO process [31]. Thus, the contribution of copper species deposited on amorphous silica in the overall catalytic performance of Cu/Ti-ITQ-6 cannot be excluded.…”

Section: Catalytic Studiesmentioning

confidence: 93%

See 1 more Smart Citation

Ferrierite and Its Delaminated Forms Modified with Copper as Effective Catalysts for NH3-SCO Process

et al. 2020

Self Cite

View full text Add to dashboard Cite

Ferrierites and their delaminated forms (ITQ-6), containing aluminum or titanium in the zeolite framework, were synthetized and modified with copper by an ion-exchange method. The obtained samples were characterized with respect to their chemical composition (ICP-OES), structure (XRD, UV-Vis DRS), textural parameters (N2-sorption), surface acidity (NH3-TPD), form and reducibility of deposited copper species (UV-Vis DRS and H2-TPR). Ferrierites and delaminated ITQ-6 zeolites modified with copper were studied as catalysts for the selective catalytic oxidation of ammonia to dinitrogen (NH3-SCO). It was shown that aggregated copper oxide species, which were preferentially formed on Ti-zeolites, were catalytically active in direct low-temperature ammonia oxidation to NO, while copper introduced into Al-zeolites was present mainly in the form of monomeric copper cations catalytically active in selective reduction of NO by ammonia to dinitrogen. It was postulated that ammonia oxidation in the presence of the studied catalysts proceeds according to the internal-selective catalytic reduction mechanism (i-SCR) and therefore the suitable ratio between aggregated copper oxide species and monomeric copper cations is necessary to obtain active and selective catalysts for the NH3-SCO process. Cu/Al-ITQ-6 presented the best catalytic properties possibly due to the most optimal ratio of these copper species.

show abstract

Section: Catalytic Studiesmentioning

confidence: 93%

“…In the first step, below 300 • C, the reduction of Cu 2+ to Cu + occurs. While in the second step, Cu + to Cu 0 is reduced at higher temperatures, typically above 400 • C [19,31]. Thus, the results of H 2 -TPR are important for an analysis of the form and aggregation of copper species present in catalysts.…”

Section: H 2 -Tprmentioning

confidence: 99%

Ferrierite and Its Delaminated Forms Modified with Copper as Effective Catalysts for NH3-SCO Process

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…It has been reported that the size and shape of MSNs can be easily tailored by varying the temperature [7,8], reactants ratio [9], pH [10], surfactant chain length [11], as well as the addition of functional organosilanes [12]. Properly tailored MSNs found applications in numerous fields such as drug delivery systems [13,14], wastewater treatment [15,16], catalysis [17,18], fabrication of nanoreactors [19,20] and nanocontainers [21,22].…”

Section: Introductionmentioning

confidence: 99%

Thermoresponsive Polymer Gating System on Mesoporous Shells of Silica Particles Serving as Smart Nanocontainers

2020

View full text Add to dashboard Cite

Spherical silica nanoparticles with solid cores and mesoporous shells (SCMS) were decorated with thermoresponsive polymer brushes that were shown to serve as macromolecular valves to control loading and unloading of a model dye within the mesopores. Thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) brushes were grafted from the surfaces of both solid core (SC) and SCMS particles of similar size using surface-initiated atom transfer radical polymerization. Both systems based on porous (SCMS-PNIPAM) and nonporous (SC-PNIPAM) particles were characterized using cryo-TEM, thermogravimetry and elemental analysis to determine the structure and composition of the decorated nanoparticles. The grafted PNIPAM brushes were found to be responsive to temperature changes enabling temperature-controlled gating of the pores. The processes of loading and unloading in the obtained systems were examined using a model fluorescent dye—rhodamine 6G. Polymer brushes in SCMS-PNIPAM systems were shown to serve as molecular valves enabling significant adsorption (loading) of the dye inside the pores with respect to the SC-PNIPAM (no pores) and SCMS (no valves) systems. The effective unloading of the fluorescent cargo molecules from the decorated nanoparticles was achieved in a water/methanol solution. The obtained SCMS-PNIPAM particles may be used as smart nanocontainers or nanoreactors offering also facile isolation from the suspension due to the presence of dense cores.

show abstract

“…Nitrogen oxides (NOx) contribute to a number of global environmental problems such as eutrophication, climate change, acid precipitation and haze, which is one of major sources of atmospheric pollutants . The increasingly stringent regulations of NOx emissions require the development of practical technologies for their removal from flue gases . Among the advanced methods for NOx emission abatement, selective catalytic reduction of NOx with NH 3 (NH 3 ‐SCR) seems to be the most prospective approach ,.…”

Section: Introductionmentioning

confidence: 99%

“…[1][2][3] The increasingly stringent regulations of NOx emissions require the development of practical technologies for their removal from flue gases. [4] Among the advanced methods for NOx emission abatement, selective catalytic reduction of NOx with NH 3 (NH 3 -SCR) seems to be the most prospective approach. [5,6] With the in-depth research about the catalysts in the NH 3 -SCR field, the superiority of transition metal oxide catalysts are gradually acknowledged.…”

Section: Introductionmentioning

confidence: 99%

NOx Removal Performance Optimization of NiMnTi Mixed Oxide Catalysts by Tuning the Redox Capability

et al. 2019

ChemCatChem

View full text Add to dashboard Cite

A series of Ni4‐xMnxTi1Oy mixed metal oxides (Ni4‐xMnxTi1‐LDO) catalysts originated from layered double hydroxides (LDHs) were fabricated and evaluated in the selective catalytic reduction of NO with NH3 (NH3‐SCR). To optimize the denitrification performance, the redox capability of catalysts was adjusted by calcining the Ni4‐xMnxTi1‐LDHs precursors with different Mn loading at different temperatures. The results revealed that calcination temperature was the secondary factor while the molar ratio of Mn to Ni was the main factor for influencing the redox properties. Among Ni4‐xMnxTi1‐LDO catalysts, the Ni2Mn2Ti1‐LDO catalyst afforded the optimal DeNOx behavior with above 90 % NOx conversion and 95 % selectivity of N2 as well as superior SO2 resistance in the wide temperature region of 150–360 °C. Multiple characterizations indicated that exceptional catalytic performance of Ni2Mn2Ti1‐LDO catalyst was highly dependent on the suitable redox capability resulted from moderate concentration of Ni3+, Mn4+ and chemisorbed oxygen Oβ in catalysts surface.

show abstract

Effective catalysts for the low-temperature NH3-SCR process based on MCM-41 modified with copper by template ion-exchange (TIE) method

Cited by 45 publications

References 45 publications

Ferrierite and Its Delaminated Forms Modified with Copper as Effective Catalysts for NH3-SCO Process

Ferrierite and Its Delaminated Forms Modified with Copper as Effective Catalysts for NH3-SCO Process

Thermoresponsive Polymer Gating System on Mesoporous Shells of Silica Particles Serving as Smart Nanocontainers

NOx Removal Performance Optimization of NiMnTi Mixed Oxide Catalysts by Tuning the Redox Capability

Contact Info

Product

Resources

About