Process of reduction of a refining catalyst before its use

Claim 1

In a process for selectively hydrogenating acetylenic and diolefinic hydrocarbons, comprising contacting said hydrocarbons with a catalyst and hydrogen, under hydrogenation conditions, the improvement wherein the catalyst is produced by a process comprising: a) in a first stage, impregnating a catalyst, containing a support and an active phase with a base of at least one metal of the group VIII of the periodic table and/or at least one metal of group IB, between 0 and 50° C., with an aqueous or organic solution of a compound that is a reducing agent selected from the group consisting of aldehydes containing 2 to 14 carbon atoms per molecule, ketones or polyketones containing 1 to 18 carbon atoms per molecule and organic acids or polyacids containing 1 to 14 carbon atoms per molecule, so as to introduce 10 ppm to 100% by weight of reducing agent in the catalyst, b) in a second stage, raising the temperature of the catalyst thus impregnated to a temperature between 100 and 150° C. and under a pressure of 1 to 10 bars, whereby reduction occurs, c) in a third stage, drying the catalyst to eliminate the impregnation solvent and the water formed in step b), wherein, during the first stage, there is added to the reducing agent at least one halocarboxylic acid, in an amount of 0.1 to 10% by weight, based on halogen, relative to the weight of the reducing agent.