| 摘要 |
<p>1,240,247. Catalytic cracking. TEXACO DEVELOPMENT CORP. 3 April, 1969 [18 June, 1968], No. 17438/69. Heading C5E. A method for the fluid catalytic cracking of a first hydrocarbon stream comprising a virgin gas oil and a second hydrocarbon stream comprising a cracked cycle gas oil comprises the steps of: (a) passing said first stream and a crystalline zeolite cracking catalyst of uniform pore size through a first elongated reaction zone under conditions such that coke is deposited on said catalyst in an amount less than 0À9 weight per cent of said catalyst; (b) passing said second stream and a crystalline zeolite cracking catalyst of uniform pore size through a second elongated reaction zone under conditions such that coke is deposited on said catalyst in an amount less than 1À2 weight per cent of said catalyst; (c) discharging the effluents from the two elongated reaction zones into a reactor containing a dense phase fluidized catalyst bed; and (d) withdrawing, stripping and regenerating catalyst from the reactor and introducing regenerated catalyst into steps (a) and (b). The zeolite may be base-exchanged with Ba, Ca, Mg, Mn or rare earths. The catalyst may also contain a silica-alumina gel or a clay.</p> |
