Patent ID: 6436278
Filing Date: 2002-08-20
Classification: C10G

Abstract:
A process for producing gasoline with an improved octane number from a hydrocarbon containing feed, comprising the following successive steps:(a) converting the feed with simultaneous hydroisomerisation of the paraffins of the feed, said feed having a sulphur content of less than 1000 ppm by weight, a nitrogen content of less than 200 ppm by weight, a metals content of less than 50 ppm by weight, an oxygen content of at most 0.2% by weight, said step being carried out at a temperature of 200-500Â° C., at a pressure of 5-25 MPa, with a space velocity of 0.1-5 hâˆ’1, in the presence of hydrogen, and in the presence of a catalyst containing at least one noble metal deposited on an amorphous acidic support, and separating at least one gasoline cut and at least one residue containing compounds with a boiling point of more than at least 340Â° C. from the effluent from step a); (b) separating iso-paraffins from said gasoline cut and producing an effluent containing normal paraffins; (c) isomerising the paraffins in at least a portion of said effluent from step b) by contact with a catalyst containing at lease one hydrodehydrogenating metal and at least one acidic solid, in the presence of hydrogen, so as to produce an effluent charged with iso-paraffins with an improved octane number; (b) catalytic dewaxing of said residue using a catalyst comprising at least one molecular sieve the microporous system of which exhibits at least one principal channel with pore openings having 9 to 10 T atoms, T being Si, Al, P, B, Ti, or Ga, alternating with an equal number of oxygen atoms, the distance between two accessible pore openings having 9 or 10 T atoms being at most 0.75 nm, an said sieve having a 2-methylononane/5-methylononane ratio of more than 5 in the n-decane test.