Katalysatorer for deshalogenering av alfa-halogenerte karboksylsyrer og fremgangsmåte for rensing av mono-alfa-halogenerte karboksylsyrer

摘要

Catalyst comprising: a) a precious metal of group 8 deposited on an inert support and having been employed for dehalogenating alpha-halogenated carboxylic acids in the presence of hydrogen: b) a precious metal of group 8 deposited on an inert support, and such that the particle size of b is very much smaller than that of a in order to make it possible to form a homogeneous mixture under the effect of the streams of alpha-halogenated carboxylic acid and hydrogen. The invention is particularly useful for regenerating palladium catalysts of purification of crude monochloroacetic acid.