Organic compounds -- part of the class 532-570 series – Organic compounds – Halogen containing
Patent
1997-05-16
1998-10-13
Yildirim, Bekir L.
Organic compounds -- part of the class 532-570 series
Organic compounds
Halogen containing
585642, 585641, C07C 1725, C07C 2104
Patent
active
058213945
DESCRIPTION:
BRIEF SUMMARY
This application is a 371 of PCT/EP95/04516, filed Nov. 15, 1995.
The invention relates to a process for converting a chlorinated alkane into at least one less chlorinated alkene by reacting the chlorinated alkane with hydrogen in the presence of a catalyst comprising a metal from group VIII and another metal on a support.
TECHNOLOGY REVIEW
International applications WO-94/07828, WO-94/07827, WO-94/07823, WO-94/07821, WO-94/07820, WO-94/07819, and WO-94/07818 describe processes for converting various chlorinated alkanes into less chlorinated alkenes by means of hydrogen in the presence of a bimetallic catalyst comprising a metal from group VIII and a metal from group IB which are deposited on a support. European Patent Application EP-A-0 640 574 describes the conversion of chlorinated alkanes into less chlorinated alkenes in the presence of a bimetallic catalyst comprising platinum and a second metal, such as lanthanum, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, indium, tin or bismuth, on a support. In these known processes, the best degrees of conversion of the chlorinated alkanes and the best selectivities as regards the production of alkenes are obtained with the bimetallic catalyst platinum-copper on active charcoal. International Application WO-94/07819 and European Patent Application EP-A-0 640 574 describe more specifically processes for converting 1,2-dichloropropane into propylene. It is evident therefrom that the bimetallic catalysts specified above do not make it possible to obtain both a high degree of conversion of 1,2-dichloropropane and a high selectivity for propylene. Moreover, these catalysts are initially of very low selectivity with respect to the formation of propylene, with a large quantity of propane being produced. Because of this, these known catalysts are unsuitable for generating propylene which can be used directly in a unit for the production of allyl chloride by chlorination of propylene. In effect, when a mixture comprising propylene and propane is recycled to the allyl chloride production stage, 1-chloropropane and/or 2-chloropropane are formed by chlorination of propane, and these products are difficult to separate from the allyl chloride. Another disadvantage of these known catalysts is their rapid deactivation. Consequently, the pretreatment of these catalysts using hydrogen chloride is necessary in order to improve their initial selectivity and their stability. The patent U.S. Pat. No. 3,892,818 discloses a process for de-chlorinating 1,2-dichloropropane using hydrogen in the presence of a bimetallic rhodium-gold catalyst supported on alumina. This catalyst has a good activity and a long life, but the reaction product is essentially propane.
SUMMARY OF THE INVENTION
A process has now been found which does not have the above-described disadvantages and which makes it possible to convert chlorinated alkanes into less chlorinated alkenes with a good selectivity and preferably with a high degree of conversion without the catalyst either becoming rapidly deactivated over time or requiring pretreatment with hydrogen chloride.
The invention consequently relates to a process for converting a chlorinated alkane into at least one less chlorinated alkene by reacting the chlorinated alkane with hydrogen in the presence of a catalyst comprising a metal from group VIII and a metal M, on a support, which is characterized in that the metal from group VIII is palladium and the metal M is selected from the group consisting of silver, gallium, indium, thallium, germanium, tin, lead, arsenic, antimony, bismuth and mixtures thereof.
DETAILED DESCRIPTION OF THE INVENTION
The chlorinated alkane employed in the process according to the invention is an alkane comprising at least one chlorine atom. Good results have been obtained with acyclic chlorinated alkanes and, more especially, with acyclic chlorinated alkanes of general formula C.sub.n H.sub.2n+2-x Cl.sub.x in which n is an integer from 2 to 6 and x is an integer from 1 to (2n+2). Chloropropanes a
REFERENCES:
patent: 3892818 (1975-07-01), Scharfe et al.
patent: 5453557 (1995-09-01), Harley et al.
patent: 5476979 (1995-12-01), Ito et al.
patent: 5498806 (1996-03-01), Ichikawa et al.
patent: 5637548 (1997-06-01), Ito et al.
Janssens Francine
Schoebrechts Jean-Paul
Solvay
Yildirim Bekir L.
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