CaltechAUTHORS
  A Caltech Library Service

Preparation of transition metal fluorides as catalysts for the environmentally sustainable HFC production

Forni, Laura and Albonetti, Stefania and Cavani, Fabrizio and Bernardi, Marco and Beghin, Alessandro and Trifirò, Ferruccio (2010) Preparation of transition metal fluorides as catalysts for the environmentally sustainable HFC production. In: Scientific bases for the preparation of heterogeneous catalysts : proceedings of the 10th International Symposium, Louvain-la-Neuve, Belgium, July 11-15, 2010. Studies in Surface Science and Catalysis. No.175. Elsevier , Amsterdam, pp. 993-1000. ISBN 978-0-444-53601-3. https://resolver.caltech.edu/CaltechAUTHORS:20150925-125116758

Full text is not posted in this repository.

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20150925-125116758

Abstract

Hydrofluorocarbons have been proposed as CFC and HCFC substitutes since 1987, after the Montreal Protocol, with the aim of decreasing the ozone depletion. At present, these compounds are industrially produced by reaction of chlorinated hydrocarbons with HF. Environmental concerns have been raised regarding such processes, due to the co-production of huge amounts of HCl and the possible generation of dioxins and chlorinated compounds [1]. Due to their contribution to the greenhouse effect, fluorinated alkanes have often been replaced by other materials (e.g., natural refrigerants) in several UE countries [1,2]. On the other hand, fluorinated olefins are used as intermediates for fluorinated polymers. A growing effort is currently being performed to set out cleaner processes for these latter compounds. To achieve an environmentally sustainable process, a possible alternative for fluorinated alkenes synthesis is the reaction of olefins with fluorinated solids. In particular, perovskites-type materials with composition (AgF)(MF_y)_x, were reported to be active catalysts in ethylene and propylene oxyfluorination [3]. However, the synthesis of the perovskite-type mixed fluoride [4,5] leads to the formation of other compounds, such as metal oxides or reduced metals (i.e., Ag^0). For this reason, we tried to improve previous results with the aim of optimizing the catalyst synthesis. This work deals with the synthesis of AgCuF_3 by i) solid state reaction between commercial fluorides, in a HF flow, and ii) fluorination with HF of an oxohydrate obtained by metal nitrates co-precipitation. These compounds were also characterized by catalytic reactivity tests. As the re-oxidation of the reduced catalyst and the completion of the catalytic cycle was hindered by the presence of metallic Ag, we also investigated the possibility to synthesize mixed perovskite-like structures starting from fluorides of Ce(IV), Fe(III), Ag(I) and Cu(II).


Item Type:Book Section
Additional Information:© 2010 Elsevier. The authors gratefully acknowledge Arkema for the financial support.
Funders:
Funding AgencyGrant Number
ArkemaUNSPECIFIED
Series Name:Studies in Surface Science and Catalysis
Issue or Number:175
Record Number:CaltechAUTHORS:20150925-125116758
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20150925-125116758
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:60532
Collection:CaltechAUTHORS
Deposited By: George Porter
Deposited On:25 Sep 2015 21:05
Last Modified:03 Oct 2019 08:57

Repository Staff Only: item control page