Abstract: A method for regenerating of rhodium-containing catalysts exhausted and sulphur-poisoned in the course of dealkylating alkyl benzenes or mixture thereof with steam or hydrogen, comprising the steps of burning out coke deposits by an oxygen-containing gas and chlorinating the catalyst with chlorine or with a chlororganic compound in a flow of hydrogen, an inert gas or a mixture of an inert gas with oxygen and moisture. The catalyst is additionally treated with ammonia or with a nitrogen-containing compound capable of decomposing under the treatment to yield ammonia in the presence of at least one component selected from the group consisting of: water, hydrogen, and nitrogen-oxygen mixture. The treatment can be conducted both in the liquid and the gaseous phases at temperatures ranging between 20.degree. and 650.degree. C. and at a pressure between 1 and 50 atm.The present invention can be used for regeneration of rhodium-containing catalysts and used for dealkylating alkyl benzenes with steam or hydrogen.

Abstract: Catalyst for dealkylating, in the presence of steam, a hydrocarbon charge, obtained for example from a catalytic reforming unit or from a unit for the production of aromatic hydrocarbons, and containing at least one alkylaromatic hydrocarbon such as toluene or a xylene, said catalyst containing an alumina carrier of a specific surface higher than 50 m.sup.2 /g and, by weight with respect to the catalyst, from 0.1 to 2% of rhodium, from 0.05 to 2% of at least one metal selected from copper, silver and gold, from 0.05 to 2% of rhenium and from 0.02 to 5% of at least one additional metal selected from lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium and uranium.

Abstract: Catalyst for dealkylating, in the presence of steam, a hydrocarbon charge, obtained for example from a catalytic reforming unit or from a unit for the production of aromatic hydrocarbons, and containing at least one alkylaromatic hydrocarbon such as toluene or a xylene, said catalyst containing an alumina carrier of a specific surface higher than 50 m.sup.2 /g and, by weight with respect to the catalyst, from 0.1 to 2% of rhodium, from 0.05 to 2% of at least one metal selected from copper, silver and gold, from 0.05 to 2% of rhenium and from 0.02 to 5% of at least one additional metal selected from lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium and uranium.

Abstract: A catalyst for dealkylating alkyl benzenes and fractions of aromatized benzines by means of steam conversion is disclosed. The catalyst comprises rhodium or rhodium in a mixture with another noble metal from Group VIII of the Periodic System in an amount of 0.1 to 2 wt. % on a carrier of aluminum oxide and also at least one of the elements selected from the group consisting of sulfur, selenium or lead in an amount of 0.003 to 3 wt. %. To increase the yield of the final product, the catalyst also comprises at least one element selected from the group containing iron, cobalt, nickel, chrome, copper, and vanadium in an amount of 0.01 to 5 wt. %, and at least one of the elements of the alkaline or alkaline earth metals or mixtures thereof in an amount of 0.01 to 5 wt. %.The proposed catalyst features a high degree of selectivity for dealkylating alkyl benzenes in combination with a high degree of starting feed conversion.

Abstract: A method of preparing benzene and xylenes from catalysates of reforming of gasoline fractions comprising a mixture of aromatic C.sub.6 -C.sub.10 hydrocarbons and non-aromatic hydrocarbons which involves separation of a low-boiling fraction boiling out at a temperature of 90.degree.-108.degree. C. from a reforming catalysate by rectification. The remaining high-boiling fraction is processed in the presence of a hydrogen-containing gas at a temperature within the range of from 450.degree. to 600.degree. C. under a pressure of from 10 to 60 atm on a catalyst. The catalyst consists of 1 to 85% by weight of H-mordenite, 0.1 to 10% by weight of a hydrogenating component as which use might be made of oxides of metals of Group VI of the periodic system, sulphides of these metals, metals of Group VIII of the periodic system, sulphides thereof; the balance being a binder.