TY - JOUR
T1 - Perovskite-Type Halo-oxide La1-xSrxFeO3-δXσ (X=F, Cl) Catalysts Selective for the Oxidation of Ethane to Ethene
AU - Dai, H. X.
AU - Ng, C. F.
AU - Au, C. T.
N1 - Funding Information:
The work described above was fully supported by a grant from the Research Grants Council of the Hong Kong Administration Region, China (Project HKBU 2050/97P). H. X. Dai thanks the HKBU for a Ph.D. studentship.
PY - 2000/1/1
Y1 - 2000/1/1
N2 - The catalytic performance and characterization of perovskite-type halo-oxide La1-xSrxFeO3-δXσ (X=F, Cl) as well as La1-x SrxFeO3-δ (x=0-0.8) for the oxidative dehydrogenation of ethane (ODE) to ethene have been investigated. XRD results indicate that the catalysts had oxygen-deficient perovskite structures and TGA results demonstrated that the F- and Cl-doped perovskites were thermally stable. Under the reaction conditions of C2H6/O2/N2=2/1/3.7, temperature=660°C, and space velocity=6000 mL h-1 g-1, C2H6 conversion, C2H4 selectivity, and C2H4 yield were, respectively, 55.3, 45.1, and 24.9% over La0.6Sr0.4FeO3-0.048; 76.8,62.1, and 47.7% over La0.8Sr0.2FeO3-0.103F0.216semi; and 84.4, 68.4, and 57.6% over La0.6Sr0.4FeO3-0.103Cl0.164. Over the two halo-oxide catalysts, with an increase in space velocity, C2H6 conversion decreased, whereas C2H4 selectivity increased. Both La0.8Sr0.2FeO3-0.103F0.216 and La0.6Sr0.4FeO3-0.103Cl0.164 were durable within 40 h of onstream ODE reaction. XPS results suggested that the presence of halide ions in the perovskite lattices promotes lattice oxygen mobility. It is apparent that the inclusion of F- or Cl- ions in La1-xSrxFeO3-δ can reduce the deep oxidation of C2H4 and thus enhance C2H4 selectivity. Based on the results of O2-TPD and TPR studies, we suggest that the oxygen species that desorbed at temperatures ranging from 590 to 700°C over the La0.8Sr0.2FeO3-0.103F0.216 and La0.6Sr0.4FeO3-0.103Cl0.164 catalysts are active for the selective oxidation of ethane to ethene. By regulating the oxygen vacancy density and the oxidation states of B-site cations by implanting halide ions into oxygen vacancies in perovskite-type oxides (ABO3), one may obtain catalysts that are durable and selective for the ODE reaction.
AB - The catalytic performance and characterization of perovskite-type halo-oxide La1-xSrxFeO3-δXσ (X=F, Cl) as well as La1-x SrxFeO3-δ (x=0-0.8) for the oxidative dehydrogenation of ethane (ODE) to ethene have been investigated. XRD results indicate that the catalysts had oxygen-deficient perovskite structures and TGA results demonstrated that the F- and Cl-doped perovskites were thermally stable. Under the reaction conditions of C2H6/O2/N2=2/1/3.7, temperature=660°C, and space velocity=6000 mL h-1 g-1, C2H6 conversion, C2H4 selectivity, and C2H4 yield were, respectively, 55.3, 45.1, and 24.9% over La0.6Sr0.4FeO3-0.048; 76.8,62.1, and 47.7% over La0.8Sr0.2FeO3-0.103F0.216semi; and 84.4, 68.4, and 57.6% over La0.6Sr0.4FeO3-0.103Cl0.164. Over the two halo-oxide catalysts, with an increase in space velocity, C2H6 conversion decreased, whereas C2H4 selectivity increased. Both La0.8Sr0.2FeO3-0.103F0.216 and La0.6Sr0.4FeO3-0.103Cl0.164 were durable within 40 h of onstream ODE reaction. XPS results suggested that the presence of halide ions in the perovskite lattices promotes lattice oxygen mobility. It is apparent that the inclusion of F- or Cl- ions in La1-xSrxFeO3-δ can reduce the deep oxidation of C2H4 and thus enhance C2H4 selectivity. Based on the results of O2-TPD and TPR studies, we suggest that the oxygen species that desorbed at temperatures ranging from 590 to 700°C over the La0.8Sr0.2FeO3-0.103F0.216 and La0.6Sr0.4FeO3-0.103Cl0.164 catalysts are active for the selective oxidation of ethane to ethene. By regulating the oxygen vacancy density and the oxidation states of B-site cations by implanting halide ions into oxygen vacancies in perovskite-type oxides (ABO3), one may obtain catalysts that are durable and selective for the ODE reaction.
KW - Ethane
KW - Ethene
KW - LaSrFeO
KW - LaSrFeOX
KW - Oxidative dehydrogenation
KW - Oxidative dehydrogenation of ethane reaction
KW - Perovskite
KW - Perovskite-type halo-oxides
UR - http://www.scopus.com/inward/record.url?scp=0001861246&partnerID=8YFLogxK
U2 - 10.1006/jcat.1999.2677
DO - 10.1006/jcat.1999.2677
M3 - Journal article
AN - SCOPUS:0001861246
SN - 0021-9517
VL - 189
SP - 52
EP - 62
JO - Journal of Catalysis
JF - Journal of Catalysis
IS - 1
ER -