Deactivation and Characterization of SCR Catalysts Used in Municipal Waste Incineration Applications

Brandin, Jan; Odenbrand, C.U. Ingemar

doi:10.1007/s10562-017-2229-8

Cited by 12 publications

(13 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At temperatures below 350 °C we observe an increased rate constant for the 890-h used material compared to the fresh catalyst. This is in line with our earlier studies on the positive effect of sulphating of the catalyst surface [29,30]. Above 400 °C the activity of the catalyst falls with the time of use or the degree of deactivation as expected.…”

Section: Catalyst Activity In the Scr Of No With Nhsupporting

confidence: 93%

“…A clear tendency to a lowering of the activation energy by deactivation is observed as has been the case in several of our earlier work [19,29,30].…”

Section: Catalyst Activity In the Scr Of No With Nhsupporting

confidence: 84%

“…They all decrease when the catalyst gets more poisoned. We have shown this fact several times before [29,30].…”

Section: The Activity In the Oxidation Of Nh 3 With Omentioning

confidence: 82%

“…More N 2 O is formed after 890 h than after 2299 h. This is probably caused by the higher rates as this catalyst is less poisoned than the latter one. Yates et al [30] studied the SCR of 1000 ppm NO with 1000 ppm NH 3 with 3% O 2 in Ar using a mass spectrometer for analysis. For a 10% V 2 O 5 /TiO 2 catalyst the selectivity to N 2 O was 9.5% at a NO conversion of 83%.…”

Section: The Selectivity In the Scr Of No With Nhmentioning

confidence: 99%

See 3 more Smart Citations

Penetration of Poisons Along the Monolith Length of a V2O5/TiO2 Diesel SCR Catalyst and Its Effect on Activity

Odenbrand

2019

Catal Lett

Self Cite

View full text Add to dashboard Cite

Catalysts used for selective catalytic reduction of NO x on diesel engines were deactivated for 890 and 2299 h in the exhausts from a diesel engine running on Swedish diesel fuel mark 1. The deactivated catalytic monoliths (100 mm long) were cut in 10 mm pieces along their axis and were characterized by physicochemical methods as well as by determination of the activity in the reduction of NO x by NH 3 and in the oxidation of NH 3 by O 2 .

show abstract

Section: Catalyst Activity In the Scr Of No With Nhsupporting

confidence: 93%

“…A clear tendency to a lowering of the activation energy by deactivation is observed as has been the case in several of our earlier work [19,29,30].…”

Section: Catalyst Activity In the Scr Of No With Nhsupporting

confidence: 84%

“…They all decrease when the catalyst gets more poisoned. We have shown this fact several times before [29,30].…”

Section: The Activity In the Oxidation Of Nh 3 With Omentioning

confidence: 82%

Section: The Selectivity In the Scr Of No With Nhmentioning

confidence: 99%

See 2 more Smart Citations

Penetration of Poisons Along the Monolith Length of a V2O5/TiO2 Diesel SCR Catalyst and Its Effect on Activity

Odenbrand

2019

Catal Lett

Self Cite

View full text Add to dashboard Cite

show abstract

“…The activation energies are decreasing with an increased degree of poisoning, as observed before [15,16]. The poisoning has the most significant effect on the formation of NO.…”

Section: Apparent Kinetic Datamentioning

confidence: 55%

The kinetics of the oxidation of ammonia on a V2O5/TiO2 SCR catalyst deactivated in an engine rig. Part I. Determination of kinetic parameters by simulation

Odenbrand

2019

Environmental Research and Technology

View full text Add to dashboard Cite

It is shown how the deactivation of a diesel SCR (Selective Catalytic Reduction) catalyst by compounds in the exhaust gases influences the kinetics of the catalyst. Results are given for the fresh (4.56 % V2O5/TiO2) catalyst and the ones used in the rig for 890 h and 2299 h. The reactions of 700 ppm NH3 and 2 % O2 in Helium yielded N2, N2O, and NO at increasing temperatures. Simulations were performed with COMSOL Multiphysics using a 3-D model of the catalyst system. The experimental values of the products N2, N2O, and NO were very nicely fitted by the kinetic model used. All three ammonia oxidation reaction rates were of the first order in the concentration of NH3. A preliminary study using non-isothermal conditions showed the maximal temperature increase to be 0.15 K. Thus, further simulations were done with an isothermal model. The deactivation reduces the pre-exponential factors and the activation energies for the formation of N2, N2O, and NO. The formation of N2 is not substantially influenced by deactivation. The changes in the kinetics of the catalytic NH3 oxidation by deactivation is reported for the first time in the present study.

show abstract

Process of SCR Catalyst Deactivation by Dimethylsiloxanes Present in Marine Fuels

Kolb,

Wesemann,

Eilts

et al. 2024

Emiss. Control Sci. Technol.

View full text Add to dashboard Cite

In recent years, there have been reports of the deactivation of selective catalytic reduction (SCR) exhaust gas catalysts after a short period of operation in marine applications. The trigger and the processes of this catalyst damage have now been investigated experimentally using a fuel burner test bench and various analysis techniques. It was found that organic silicon compounds (OSCs), which are present in marine fuels after use in mineral oil extraction and processing, cause the catalyst deactivation. In practice, these are predominantly dimethylsiloxanes. By the burner experiments, it was found that the OSCs were completely converted into combustion products, in particular SiO2. Measurements of particle size distributions and particle number concentrations up- and downstream of the catalyst showed that SiO2 particles < 20 nm in particular were retained in the catalyst. This filtration effect decreased until no further reduction was observed for particles > 50 nm. Other inorganic, particulate, SiO2-containing fuel impurities (catalyst fines) had no poisoning effect here, as these particles are mostly > 50 nm. The small particles formed a closed SiO2 layer with a thickness of approx. 5 µm on the catalyst surface which grew from the catalyst inlet to the outlet and blocked the catalyst as a diffusion barrier. As the SiO2 layer increased, the NO conversion rate decreased. The poisoning effects were observed experimentally at OSC concentrations of 5 to 60 mg Si kg−1 fuel. A field-aged catalyst that had been operated on board of a merchant ship revealed the same findings.

show abstract

Deactivation and Characterization of SCR Catalysts Used in Municipal Waste Incineration Applications

Cited by 12 publications

References 41 publications

Penetration of Poisons Along the Monolith Length of a V2O5/TiO2 Diesel SCR Catalyst and Its Effect on Activity

Penetration of Poisons Along the Monolith Length of a V2O5/TiO2 Diesel SCR Catalyst and Its Effect on Activity

The kinetics of the oxidation of ammonia on a V2O5/TiO2 SCR catalyst deactivated in an engine rig. Part I. Determination of kinetic parameters by simulation

Process of SCR Catalyst Deactivation by Dimethylsiloxanes Present in Marine Fuels

Contact Info

Product

Resources

About