Metal Fluorides, Metal Chlorides and Halogenated Metal Oxides as Lewis Acidic Heterogeneous Catalysts. Providing Some Context for Nanostructured Metal Fluorides

Abstract

Aspects of the chemistry of selected metal fluorides, which are pertinent to their real or potential use as Lewis acidic, heterogeneous catalysts, are reviewed. Particular attention is paid to β-aluminum trifluoride, aluminum chlorofluoride and aluminas γ and η, whose surfaces become partially fluorinated or chlorinated, through pre-treatment with halogenating reagents or during a catalytic reaction. In these cases, direct comparisons with nanostructured metal fluorides are possible. In the second part of the review, attention is directed to iron(III) and copper(II) metal chlorides, whose Lewis acidity and potential redox function have had important catalytic implications in large-scale chlorohydrocarbons chemistry. Recent work, which highlights the complexity of reactions that can occur in the presence of supported copper(II) chloride as an oxychlorination catalyst, is featured. Although direct comparisons with nanostructured fluorides are not currently possible, the work could be relevant to possible future catalytic developments in nanostructured materials.

Investigating the Acid Site Distribution of a New-Generation Methyl Chloride Synthesis Catalyst

“…Following a series of investigations connected with the use of η-Al 2 O 3 as a methyl chloride synthesis catalyst, 3,8−16 in 2016, McInroy and co-workers proposed a mechanism for methyl chloride production over this material. 17 Furthermore, as part of an academic/industrial collaboration, the work additionally considered a role for chemical modifiers to improve product selectivity.…”

Metal chloride cathodes for next-generation rechargeable lithium batteries

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MgF2-Based Organized Porous Inorganic Nanofluorides as Heterogeneous Catalysts for Fluorination of 2-Chloropyridine

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