Process for the production of gasolines with low sulfur contents

Process for the production of gasoline with a low sulfur content that comprises at least the following stages:

• a1) at least a selective hydrogenation of diolefins that are present in the starting gasoline,
• b) at least one separation of the gasoline that is obtained in stage a1 in two fractions, one that is virtually lacking in sulfur and that contains the lightest olefins of the starting gasoline (light gasoline), and the other in which the majority of the sulfur-containing compounds that are initially present in the starting gasoline is concentrated (heavy gasoline).
• c) at least one treatment of the heavy gasoline that is separated in stage b on a catalyst that makes it possible to decompose or to hydrogenate at least partially the unsaturated sulfur-containing compounds, under conditions where the hydrogenation of the olefins on this catalyst is limited,
• d) at least one treatment of the heavy gasoline that is obtained in stage c, without eliminating the H2S that is formed during this stage, on a catalyst that makes it possible to decompose the unsaturated sulfur-containing compounds that are not transformed in c, and more preferably the linear and/or cyclic saturated sulfur-containing compounds, with a limited hydrogenation of olefins.