Halide-doped perovskite-type AMn1−xCuxO3−δ (A = La0.8Ba0.2) catalysts for ethane-selective oxidation to ethene

摘要: Abstract The undoped and halide-doped perovskite-type oxide AMn 1− x Cu O 3− δ (A=La 0.8 Ba 0.2 ) catalysts have been investigated for the oxidative dehydrogenation of ethane (ODE) to ethene. Under reaction conditions temperature=680°C, C 2 H 6 /O /N molar ratio=2/1/3.7, space velocity=6000 ml h −1  g , 0.7 0.3 2.808 F 0.124 showed 49.2% conversion, 66.8% 4 selectivity, 32.9% yield; 2.817 Cl 0.114 73.0% 69.5% 50.8% yield. sustainable performance during a period 48 h on-stream at 680°C demonstrated that F- Cl-doped are durable. We also observed addition halide ions perovskites could reduce deep ethene oxidation. X-ray powder diffraction results indicated =0.3 X σ (X=F,Cl) were single-phase cubic in structure; when value exceeded 0.7, there trace amounts La CuO and/or phases besides perovskite phase. Mn oxidation state titration photoelectron spectroscopic studies (i) surface bulk compositions rather similar (ii) 4+ 3+ 2+ catalysts. Oxygen temperature-programmed desorption illustrated doping would result disappearance oxygen adspecies promotion lattice activity. 18 O/ 16 isotopic exchange incorporation into enhanced activity oxygen. outcome - -pulsing investigations adsorbed species prone induce complete oxidation, while active selective