Selective monochlorination of methane over solid acid and zeolite catalysts

I. Bucsi, George A. Olah

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

Chlorination of methane was studied over amorphous silica-alumina, silicalite as well as H-mordenite, X, Y, NaL and H-ZSM-5 zeolite catalysts. The heterogeneous transformations were carried out in a continuous flow reactor in the 200-425 °C temperature range, under atmospheric pressure (methane to chlorine ratio 4:1, GHSV 600 ml/ g h). Chlorination of methane over zeolites in the 200-300 °C temperature range proceeds without selectivity indicating a radical mechanism. Above 300-350 °C, depending on the nature of zeolite, selective monochlorination takes place indicating the dominance of an ionic mechanism. H-mordenite was found to give the best monochlorination at the lowest temperature (99.2% CH3Cl at 350 °C). The observed selectivity of the investigated zeolites is strongly time limited. All investigated catalysts lose their selectivity after five hours on-stream due to extraction of aluminum from the framework of zeolites by hydrogen chloride. Amorphous silica-alumina above 350 °C also catalyzes ionic chlorination. The chlorination of methane over silicalite proceeds via the nonselective radical pathway at the investigated temperatures.

Original languageEnglish
Pages (from-to)27-38
Number of pages12
JournalCatalysis Letters
Volume16
Issue number1-2
DOIs
Publication statusPublished - Mar 1992

Fingerprint

Zeolites
chlorination
Chlorination
Methane
methane
zeolites
catalysts
acids
Catalysts
Acids
Aluminum Oxide
selectivity
Silicon Dioxide
Alumina
aluminum oxides
Silica
silicon dioxide
Temperature
hydrogen chlorides
Hydrochloric Acid

Keywords

  • chlorination
  • Methane
  • solid acid
  • zeolites

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Catalysis

Cite this

Selective monochlorination of methane over solid acid and zeolite catalysts. / Bucsi, I.; Olah, George A.

In: Catalysis Letters, Vol. 16, No. 1-2, 03.1992, p. 27-38.

Research output: Contribution to journalArticle

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