Alkene oligomerization process

A process for oligomerising alkenes having from 3 to 6 carbon atoms which comprises contacting a feedstock comprising

• a) one or several alkenes having x carbon atoms, and
• b) optionally, one or several alkenes having y carbon atoms, x and y being different,
• with a catalyst containing a zeolite of the MFS structure type, under conditions to obtain selectively an oligomeric product, in which
• i) when the feedstock contains only alkenes having x carbon atoms, said oligomeric product contains at least 60 wt % of oligomers having 2x or 3x carbon atoms, or
• ii) when the feedstock contains alkenes having x carbon atoms and alkenes having y carbon atoms, said oligomeric product contains a mixture of oligomers containing predominant amounts of oligomers having x+y carbon atoms and of oligomers having 2x or 3x carbon atoms,
• the percentages by weight being expressed with respect to the total weight of alkenes in the feedstock,
• wherein the process is carried out at a temperature of from 125 to 1 75° C. when the feedstock contains only alkenes with 3 carbon atoms and of from 140 to 240° C. when the feedstock comprises at least one alkene with 4 or more carbon atoms.