Patent ID: 6660895
Filing Date: 2003-12-09
Classification: B01J,C10G

Abstract:
A process for producing aromatic compounds from a hydrocarbon cut using a catalyst circulating in a moving bed, the process comprising at least the following successive steps:a first step for treating the cut employing a naphthene dehydrogenation reaction carried out in the presence of hydrogen in a ratio (H2)1/HC where ((H2)1 represents the molar quantity of pure hydrogen expressed as hydrogen introduced into said first step and HC represents the molar quantity of feed introduced into said first step; followed by at least one subsequent treatment step carried out in the presence of hydrogen in a mole ratio (H2)2/(HC)2, where (H2)2 represents the molar quantity of hydrogen expressed as pure hydrogen introduced into said subsequent step and (HC)2 represents the molar quantity of feed entering said subsequent step; separating the gaseous hydrogen-containing effluent from the liquid product and the catalyst, recycling at least a first portion of the gaseous hydrogen-containing effluent containing at least 10% by volume of impurities, termed the recycle gas, to said first treatment step; regenerating and reducing the catalyst then re-introducing the catalyst into said first treatment step, reduction taking place in the presence of hydrogen in a mole ratio (H2)red/HC where (H2)red represents the quantity of hydrogen expressed as pure hydrogen introduced into the reduction step; characterized in that at least a second portion of the recycle gas is recycled to the reduction step and in a sufficient volume so as to eliminate substantially all heat caused by cracking of impurities and so that the gas entering the reduction step contains at least 10% by volume impurities.