Catalytic properties of La[sub 1[minus]x] Sr[sub x]BO[sub 3] (B [equals] Mn, Fe, Co, Ni) for toluene oxidation

Journal Article · Sun Oct 31 23:00:00 EST 1993 · Industrial and Engineering Chemistry Research; (United States)

OSTI ID:5626684

Liang, Jengjong; Weng, Hungshan ^[1]

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1. National Cheng Kung Univ., Tainan (Taiwan, Province of China). Dept. of Chemical Engineering

The alkaline coprecipitation method was employed to prepare La[sub 1[minus]x]Sr[sub x]BO[sub 3] (X = 0--1 and B = Mn, Fe, Co, Ni). The activities of the resulting catalysts for oxidizing toluene were measured by a differential flow reactor, and their physical properties were characterized by BET, XRD, AES, SIMS, XPS, SEM, TGA/DTGA, and stepwise oxygen desorption. The results indicate that substitution of La by Sr affects activity due to the oxygen vacancy. Among the Co and Fe series catalysts, those for which x = 0.3 demonstrate the highest activity. The catalytic activity of the Mn series catalysts was found to increase not only with the quantity of Mn atoms but also with the sum of Mn and 0 atoms. In this series, the amount of chemically adsorbed oxygen, instead of the lattice oxygen, plays an important role in the catalytic activity, especially in the temperature range of toluene oxidation, with the catalytic activity for toluene oxidation increasing with the amount of oxygen chemically adsorbed. The activity of the Ni series catalysts does not increase with increasing amounts of NiO and La[sub 2]NiO[sub 4]; the highest activity occurs at x = 0.5. The experimental results are discussed in terms of the role played by various B-site cations, the influence of catalytic surface composition on catalytic activity, and the effect of lattice and chemically adsorbed oxygen. Four influencing factors on the catalytic activity of these four series catalysts were discriminated by analysis of the results of kinetic measurements and by surface characterization.

• OSTI ID: 5626684
• Journal Information: Industrial and Engineering Chemistry Research; (United States), Journal Name: Industrial and Engineering Chemistry Research; (United States) Vol. 32:11; ISSN IECRED; ISSN 0888-5885
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020400* -- Petroleum-- Processing
ALKYLATED AROMATICS
AROMATICS
BORATES
BORON COMPOUNDS
CATALYTIC EFFECTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COBALT
ELEMENTS
HYDROCARBONS
IRON
KINETICS
LANTHANUM
MANGANESE
METALS
NICKEL
ORGANIC COMPOUNDS
OXIDATION
OXYGEN COMPOUNDS
PEROVSKITES
PHYSICAL PROPERTIES
RARE EARTHS
REACTION KINETICS
TOLUENE
TRANSITION ELEMENTS