| abstract |
The invention relates to the use in disproportionation of alkylaromatic hydrocarbons, and preferably disproportionation of toluene to produce benzene and xylenes, and / or in transalkylation of alkylaromatic hydrocarbons, and preferably the transalkylation of toluene and trimethylbenzenes producing xylenes, of a catalyst comprising at least one zeolite of the mazzite structural type, in acid form, the catalytic properties of which have been modified by deposition, on the external surface of its crystals, of at least one metal chosen from metals of group lla, such as Be, Mg, Ca, Sr or Ba, of group IVb, such as Ti, Zr or Hf, of group IIb such as Zn, Cd or Hg and of group IVa such as Ge, Sn or Pb of the periodic classification of the elements, said catalyst also comprising at least one matrix and optionally at least one element taken from the assembly formed by groups IB and VIII of the periodic classification of the elements. |