The present invention relates to an integrated process for the preparation in
continuous of epoxides which comprises: (a) preparing an alcoholic or hydro-alcoholic
solution of hydrogen peroxide in a concentration of over 3% by weight, using a
gaseous stream containing hydrogen, oxygen and an inert gas, in the presence of
a bimetallic catalyst based on palladium and platinum as active components; (b)
putting the alcoholic or hydro-alcoholic solution of hydrogen peroxide obtained
in step (a) in contact with an olefin and a buffering agent, in the presence of
an epoxidation catalyst suspended in the reaction solvent, in order to obtain a
reaction mixture containing the epoxide corresponding to the olefin, water and
alcoholic solvent; (c) treating the alcoholic stream leaving step (b), after separation
of the epoxide, in order to eliminate the nitrogenated compounds present; (d) feeding
the alcoholic solvent obtained in (c) to step (a). The process may comprise a further
step (e), wherein the raw hydro-alcoholic mixture of the flash column bottom, is
used, when necessary, for diluting the alcoholic or hydro-alcoholic solution of
hydrogen peroxide obtained in step (a) to the value required by the epoxidation
plant. The process operates under high safety conditions and with a high overall
efficiency, in terms of productivity and selectivity.
