Patent ID: 8524961

Claim:
A process for improving p-xylene production comprising the steps of: producing a naphtha fraction and a light cycle oil fraction from a fluid catalytic cracking zone; combining the naphtha and light cycle oil fractions; hydrotreating the combined naphtha and light cycle oil fractions to produce a hydrotreated product; fractionating the hydrotreated product in a fractionation zone to make a light ends cut, a naphtha cut, a hydrocracker feed and an unconverted oil fraction; sending the hydrocracker feed to a hydrocracking zone to make a hydrocracker product; recycling the hydrocracker product to the fractionation zone, feeding the hydrocracker product above an outlet for the hydrocracker feed, but below an outlet for the naphtha cut; sending the naphtha cut to a dehydrogenation zone, the dehydrogenation zone comprising a first portion of regenerated reforming catalyst from a catalyst regenerator; moving the regenerated reforming catalyst downward through the dehydrogenation zone as it cokes to become lightly coked catalyst; sending a product stream of the dehydrogenation zone to an aromatics extraction unit; withdrawing an aromatic-rich extract and a raffinate from the aromatics extraction unit; heating a straight run naphtha and the raffinate and feeding them to a first reforming zone, the first reforming zone comprising a second portion of regenerated reforming catalyst from the catalyst regenerator; moving the regenerated reforming catalyst downward through the first reforming zone as it starts to become lightly coked catalyst; removing the lightly coked catalyst from the first reforming zone and the dehydrogenation zone and feeding the lightly coked catalyst from both the first reforming zone and the dehydrogenation zone to the top of the second reforming zone; heating an effluent from the first reforming zone and feeding it to a second reforming zone; moving the lightly coked reforming catalyst downward through the second reforming zone as it becomes partially coked reforming catalyst; removing the partially coked reforming catalyst from the second reforming zone and feeding it to a third reforming zone; heating an effluent from the second reforming zone and feeding it to the third reforming zone to produce a reformate, the third reforming zone comprising the partially spent reforming catalyst; moving the partially spent reforming catalyst downward through the third reforming zone as it becomes a substantially spent catalyst; removing the substantially spent reforming catalyst from the third reforming zone; regenerating the substantially spent reforming catalyst from the third reforming zone in the catalyst regenerator; and feeding the dehydrogenated naphtha to an aromatics recovery unit to recover p-xylene and other aromatics.