Research output: Contribution to journal › Article › peer-review
Effect of Alumina Phase Transformation on Stability of Low-Loaded Pd-Rh Catalysts for CO Oxidation. / Vedyagin, Aleksey A.; Volodin, Alexander M.; Stoyanovskii, Vladimir O. et al.
In: Topics in Catalysis, Vol. 60, No. 1-2, 02.2017, p. 152-161.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Effect of Alumina Phase Transformation on Stability of Low-Loaded Pd-Rh Catalysts for CO Oxidation
AU - Vedyagin, Aleksey A.
AU - Volodin, Alexander M.
AU - Stoyanovskii, Vladimir O.
AU - Kenzhin, Roman M.
AU - Plyusnin, Pavel E.
AU - Shubin, Yury V.
AU - Mishakov, Ilya V.
PY - 2017/2
Y1 - 2017/2
N2 - Bimetallic Pd-Rh catalysts with precious metal loading of 0.2 wt% was prepared by incipient wetness impregnation of the support (γ-Al2O3or δ-Al2O3) with dual complex salt [Pd(NH3)4]3[Rh(NO2)6]2. Monometallic Pd and Rh catalysts as well as its mechanical mixture were used as the reference samples. All samples were exposed for in situ prompt thermal aging procedure, and characterized by EPR spectroscopy, UV–Vis diffuse reflectance spectroscopy and photoluminescence spectroscopy. The nature of the support was found to have strong effect on high temperature stability of the samples. δ-Al2O3having non-uniform phase structure due to presence of θ-Al2O3and α-Al2O3traces causes the concentrating of rhodium near the interphase boundary, thus changing the mechanism of Rh3+bulk diffusion if compare with γ-Al2O3. No noticeable anchoring effects were observed for bimetallic Pd-Rh samples neither in terms of Rh bulk diffusion nor with regard to the Pd sintering. It has been found experimentally that phase transformation of γ-Al2O3at high temperatures does not play dramatic role for the deactivation of bimetallic Pd-Rh active species anchored to the electron-donor site of the support.
AB - Bimetallic Pd-Rh catalysts with precious metal loading of 0.2 wt% was prepared by incipient wetness impregnation of the support (γ-Al2O3or δ-Al2O3) with dual complex salt [Pd(NH3)4]3[Rh(NO2)6]2. Monometallic Pd and Rh catalysts as well as its mechanical mixture were used as the reference samples. All samples were exposed for in situ prompt thermal aging procedure, and characterized by EPR spectroscopy, UV–Vis diffuse reflectance spectroscopy and photoluminescence spectroscopy. The nature of the support was found to have strong effect on high temperature stability of the samples. δ-Al2O3having non-uniform phase structure due to presence of θ-Al2O3and α-Al2O3traces causes the concentrating of rhodium near the interphase boundary, thus changing the mechanism of Rh3+bulk diffusion if compare with γ-Al2O3. No noticeable anchoring effects were observed for bimetallic Pd-Rh samples neither in terms of Rh bulk diffusion nor with regard to the Pd sintering. It has been found experimentally that phase transformation of γ-Al2O3at high temperatures does not play dramatic role for the deactivation of bimetallic Pd-Rh active species anchored to the electron-donor site of the support.
KW - Alumina
KW - Bimetallic Pd-Rh catalysts
KW - CO oxidation
KW - Deactivation
KW - Phase transformation
KW - Stability
KW - Thermal aging
KW - PD/AL2O3
KW - PALLADIUM
KW - CE
KW - PR
KW - PERFORMANCE
KW - BEHAVIOR
KW - SITES
KW - OXYGEN STORAGE CAPACITY
UR - http://www.scopus.com/inward/record.url?scp=85013908893&partnerID=8YFLogxK
U2 - 10.1007/s11244-016-0726-4
DO - 10.1007/s11244-016-0726-4
M3 - Article
AN - SCOPUS:85013908893
VL - 60
SP - 152
EP - 161
JO - Topics in Catalysis
JF - Topics in Catalysis
SN - 1022-5528
IS - 1-2
ER -
ID: 10278952