A Quantum-Chemical MINDO/3 Study of Methane and Oxygen Interactions with a Pure and a Modified Calcium Oxide Surface Full article
Journal |
Journal of Molecular Catalysis A: Chemical
ISSN: 1381-1169 |
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Output data | Year: 1995, Volume: 101, Number: 1, Pages: 51-60 Pages count : 10 DOI: 10.1016/1381-1169(95)00042-9 | ||||||
Tags | Adsorption, Calcium oxide, Methane, Oxygen, Quantum-chemical study | ||||||
Authors |
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Affiliations |
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Funding (1)
1 | German Research Foundation |
Abstract:
Within the framework of the MINDO/3 method methane and oxygen interactions with pure and modified calcium oxide have been considered. It is shown that low-coordinated Ca2+3C-O2−4C and Ca2+4C-O2−3C pairs of acid-base centers are responsible for the initial step in the methane activation on pure calcium oxide. Atomic oxygen strongly adsorbs only on surface basic sites yielding surface O2−2 species. Molecular oxygen adsorbs both on acid and basic sites and forms either π-complexes or O3 species, respectively. However, the dissociative adsorption of molecular oxygen on adjacent pairs of basic sites is energetically more favorable. The energetics of the substitution of a Ca2+LC ion by Mg2+LC in Mg/CaO, Na+LC in Na/CaO and Zn2+LC in Zn/CaO and Na/Zn/CaO and the methane activation on these modified calcium oxides have also been considered. The results allow an understanding of the experimentally observed increase of the C2+ hydrocarbon selectivity in the oxidative coupling of methane both on mixed magnesium and calcium oxides containing 10 to 15% of CaO and on NaOH-promoted CaO catalysts containing minor amounts of Zn2+ cations.
Cite:
Zhanpeisov N.U.
, Staemmler V.
, Baerns M.
A Quantum-Chemical MINDO/3 Study of Methane and Oxygen Interactions with a Pure and a Modified Calcium Oxide Surface
Journal of Molecular Catalysis A: Chemical. 1995. V.101. N1. P.51-60. DOI: 10.1016/1381-1169(95)00042-9 WOS Scopus РИНЦ
A Quantum-Chemical MINDO/3 Study of Methane and Oxygen Interactions with a Pure and a Modified Calcium Oxide Surface
Journal of Molecular Catalysis A: Chemical. 1995. V.101. N1. P.51-60. DOI: 10.1016/1381-1169(95)00042-9 WOS Scopus РИНЦ
Dates:
Submitted: | Aug 30, 1994 |
Accepted: | Feb 21, 1995 |
Published print: | Jul 29, 1995 |
Published online: | Dec 22, 1999 |
Identifiers:
Web of science | WOS:A1995RP50600008 |
Scopus | 2-s2.0-0002647128 |
Elibrary | 30845136 |
Chemical Abstracts | 1995:727102 |
Chemical Abstracts (print) | 123:227390 |
OpenAlex | W2043757985 |