Process for the catalytic hydrodealkylation of alkylaromatic hydrocarbons

A process for the catalytic hydrodealkylation of alkylaromatic hydrocarbons, conducted at a temperature from 400.degree. to 650.degree. C in the presence of hydrogen, under a pressure from 1 to 40 kg/cm.sup.2, with a spatial velocity from 1 to 10 and a ratio of the hydrogen to the hydrocarbon, expressed in moles by mole at the outlet of the reactor from 1 to 10, and in the presence of a catalyst selected from one of the catalysts A and B, in which:

• catalyst A essentially contains:
• a. a carrier,
• b. at least one metal selected from a first group consisting of cobalt, ruthenium, osmium, palladium, rhodium, iridium and platinum, at a metal concentration from 0.05 to 20% by weight of catalyst when the selected metal is cobalt and from 0.05 to 5% by weight of the catalyst when the selected metal is chosen from the group consisting of ruthenium, osmium, palladium, rhodium, iridium and platinum,
• c. at least one additional metal selected from a second group consisting of zinc, cadmium, gallium, indium, thallium, manganese, silver, gold, yttrium, titanium, niobium and tantalum, said metal being at a concentration from 0.05 to 5% by weight of the catalyst;
• catalyst B contains essentially:
• a. a carrier,
• b. at least one metal selected from a first group consisting of chromium, molybdenum, tungsten, rhenium and manganese, the metal concentration being from 0.05 to 20% by weight of the catalyst.
• c. at least one additional metal, said additional metal being chosen different from the selected metal of the first group, this additional metal being selected from the group consisting of chromium, molybdenum, tungsten, rhenium, manganese, copper, gold, zinc, cadmiun, gallium, indium, thallium, germanium, the metal concentration being from 0.05 to 20% by weight of the catalyst.