TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The catalyst consists of a ZSM-5 zeolite in bound form, with binders selected from aluminas such as pseudo-bohemite and gamma-alumina, clays such as kaolinite, smectites, montmorillonites; silica; alumino-silicates; titanium and zirconium oxides with zeolite/binder weight ratios of 100/1 to 1/10. The ZSM-5 zeolite has Si/Al molar ratio of 5 to 70 (preferably 5 to 35). The overall content of the metals platinum and molybdenum is 0.5-4 wt.%. Preferred Method: The metal dispersion on the catalyst is carried out according to techniques selected from impregnation, ion exchange, vapor deposition or surface adsorption. The ZSM-5 zeolite as such or in bound form, is impregnated with solutions of the salts of the metals platinum and molybdenum, subsequently dried and then calcined at 400 to 650degreesC, obtaining a Ptx-Moy/ZSM-5 catalyst. The impregnation of the ZSM-5 zeolite as such or in bound form is effected using an aqueous or aqueous-organic solution, with the organic solvent selected from alcohols, ketones and nitriles or their blends, containing hydro- or organo-soluble compounds of the metals, in such a concentration that the overall metal content in the catalyst is 0.1 to 10 wt.%.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The hydro-dealkylation reaction takes place at 450 to 580degreesC, pressures of 2.8 to 3.6 MPa, H2/feedstock molar ratios of 3.8 to 5.2, and flow-rates of the reagents so as to guarantee a Liquid Hourly Space Velocity (LHSV) calculated on the hydrocarbon stream, of 3 to 5 hour-1 (preferably 3.5 to 4.5 hour-1). Preferred Components: The 8-13C alkyl-aromatic hydrocarbon feedstock comes from a reforming unit or a unit which effects pyrolysis processes or from steam-cracking. The hydrocarbon feedstock subjected to hydro-dealkylation comprises 8-13C alkyl-aromatic compounds mixed with 4-10C aliphatic and cycloaliphatic products, which are aromatized and then hydrodealkylated under the process conditions and organic compounds containing heteroatoms. The hydrocarbon feedstock subjected to hydro-dealkylation comprises 8-13C alkylaromatic compounds selected from ethyl-benzene, xylenes, propyl-benzenes, ethyl-toluenes, trimethyl-benzenes, diethyl-benzenes, ethyl-xylenes, tetramethyl-benzenes, propyl-toluenes, ethyl-trimethyl-benzenes, triethyl-benzenes, dipropyl-toluenes and 4-10C aliphatic and cycloaliphatic compounds which, under the process conditions, are aromatized and then hydrodealkylated, such as butanes, pentanes, hexanes, heptanes and relative cyclic and cycloalkyl compounds. EXAMPLE - A catalyst A was prepared by mixing a ZSM-5 zeolite having a silicon (Si)/aluminum (Al) molar ratio of 30 and an alumina as binder, where the two phases were in a 60/40 weight ratio, and extruding the mixture. The extruded product was calcined in air at 550degreesC for 5 hours and its BET surface area was 290 m2/g. Once this had reached room temperature, it was crushed and sieved to produce a powder having dimension of 20 to 40 mesh (between 0.84 and 0.42 mm), so that 12.4 g of catalyst powder occupy an equivalent volume of 20 ml. A catalyst D was obtained by impregnating 'catalyst A' (50 g) in two steps: a first impregnation with an aqueous solution (60 ml) containing 0.69 g of ammonium molybdate, followed by second impregnation with an aqueous solution (50 ml) containing 0.25 platinum tetraminonitrate. The impregnation procedure with the first metal was effected without calcination, followed by impregnation with the second metal with the same operative procedures, followed by the final calcination in air at 550degreesC for 5 hours. The molybdenum and platinum content in the catalyst was calculated as being 0.75 wt.% and 0.25 wt.% respectively compared with the values of 0.76 wt.% and 0.23 wt.% obtained by ICP-MS. A reactor was charged with 20 cm3 (12.4 g) of catalyst D/catalyst A, whereas the rest of the volume was filled with corundum in granules, in order to guarantee optimum distribution and mixing of the gaseous flow of reagents and of the heat supplied to the reaction. A feedstock comprising (wt.%): toluene (6.6), ethyl benzene (31.4), ortho, meta, para-xylene (10.5), indane (16.1), propyl benzenes (n-, iso-) (6.9), ethyl-toluenes (2-, 3-, 4-) (8.8), other 9C or 9C+ aromatic products (5.1), 4-10C aliphatic products (14.6) was fed to the reactor mixed with hydrogen and pre-heated to 280degreesC. The reaction was carried out at a pressure of 3 MPa, with a reagent feedstock flow-rate which was such as to obtain a LHSV of 3.9-4.1 hour-1, and a H2/feedstock molar ratio of 4.5. The results for catalyst D/catalyst A were: selectivity to benzene+toluene = 76.7/66.6 wt.%; selectivity to benzene+toluene+ethane = 98.9/83.9 wt.%. The results showed that catalyst D showed better results than catalyst A.