Res. Chem. Intermed.
, Vol. 29, No. 1, pp. 71–81 (2003)
Also available online - www.vsppub.com
Microwave-enhanced dechlorination of chlorobenzene
MARILENA T. RADOIU
, IOAN CALINESCU
, DIANA I. MARTIN
and RODICA CALINESCU
National Institute for Lasers, Plasma and Radiation Physics, Electron Accelerator Laboratory,
P.O. Box MG36 Magurele, Bucharest R76900, Romania
Polytechnic University of Bucharest, Industrial Chemistry Faculty, Calea Victoriei 149,
Bucharest R71101, Romania
Received 10 April 2002; accepted 20 May 2002
Abstract—Heterogeneous liquid-phase dechlorination of chlorobenzene over supported palladium-
based catalysts to form benzene was examined using microwave and conventional heating methods.
The reaction was carried out in a solution of NaOH in 2-propanol at atmospheric pressure and re ux
temperature (approx. 83
C). Two types of commercial aluminium-silicate and ° -alumina-supported
catalysts have been tested. The results obtained under microwave (MW) and conventional (CH)
conditions were compared with respect to the rate enhancement, selectivity and catalyst activity. The
sole product of the chlorobenzene dehalogenation was benzene. The effect of the addition of NaOH
has been analysed for the neutralisationof HCl.
: Chlorobenzene; microwave activation; palladium catalyst; dechlorination.
The catalytic conversion of aromatic halides (Ar-X) for the abatement of organic
waste containing halogen has attracted increasing attention in recent years, due to
both environmental and economic considerations.
Conventional research on the removal of halogenated aliphatic and aromatic
hydrocarbon compounds from uid waste streams includes reactions catalysed by
supported noble metal-based catalysts, typically in the gas phase or in organic
liquids. Recent studies have focussed on the dechlorination of aromatic compounds
in 2-propanol. It has been observed that the dechlorination rates increased with
decreasing number of chlorine substituents . In this transformation 2-propanol
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