Abstract: The present invention discloses a catalytic cracking process of petroleum hydrocarbons and a tube-in-tube riser reactor used therein. In the present invention, a catalyst is fed via an inlet conduit to an inner tube and an annular space between the inner and outer tubes of the tube-in-tube riser reactor to contact a hydrocarbon feedstock, and the hydrocarbon feedstock is cracked under FCC conditions, then a reaction stream thus produced flows into a separation apparatus via a confluence tube to separate a hydrocarbon product stream from a spent catalyst, the spent catalyst is stripped and regenerated, then a regenerated catalyst is recycled for reuse. The process of the present invention can improve both product distribution and product properties.

Abstract: This invention relates to a process for catalytically upgrading light petroleum hydrocarbons accompanied by low temperature regenerating the catalyst, which comprises injecting the light petroleum hydrocarbons into a catalytic cracking reactor, contacting the light petroleum hydrocarbons with a regenerated catalyst and carrying out the reaction, separating the reaction products regenerating the stripped catalyst for 10 to 50 minutes under the regeneration conditions of a temperature of 400 to 600° C. and a pressure of 0.1 to 0.6Mpa; recycling the regenerated catalyst into the reactor. The process of the present invention can reduce the olefin content of gasoline, increase the cetane number of diesel oils, and decrease the contents of sulfur and nitrogen to some extent.

Abstract: This discloses a process for catalytically cracking hydrocarbon stocks in a riser or fluidized bed reactor simultaneously to increase yields of diesel and liquefied gas. The process includes the steps of: first, charging a gasoline stock and a catalytic cracking catalyst into a lower zone of the reactor to permit contact between the catalyst and the gasoline stock and to produce a liquefied gas-rich oil-gas mixture containing reacted catalyst. The resulting liquefied gas-rich oil-gas mixture (still containing reacted catalyst) is then introduced into a reaction zone above the lower zone of the reactor. Simultaneously, at least one conventional catalytic cracking hydrocarbon feed is also fed independently into at least two sites is situated at a different height above the lower zone of the reactor. The resulting mixture is then separated in a conventional fashion.