A process for the catalytic cracking of hydrocarbon oils includes the step of contacting a hydrocarbon oil feedstock with a catalytic cracking catalyst in a reactor having one or more fast fluidized reaction zones for reaction. At least one of the fast fluidized reaction zones of the reactor is a full dense-phase reaction zone, and the axial solid fraction ε of the catalyst is controlled within a range of about 0.1 to about 0.2 throughout the full dense-phase reaction zone. When used for catalytic cracking of hydrocarbon oils, particularly heavy feedstock oils, the process, reactor and system show a high contact efficiency between oil and catalyst, a selectivity of the catalytic reaction, an effectively reduced yield of dry gas and coke, and an improved yield of high value-added products such as ethylene and propylene.

A process for the catalytic cracking of hydrocarbon oils includes the step of contacting a hydrocarbon oil feedstock with a catalytic cracking catalyst in a reactor having one or more fast fluidized reaction zones for reaction. At least one of the fast fluidized reaction zones of the reactor is a full dense-phase reaction zone, and the axial solid fraction ε of the catalyst is controlled within a range of about 0.1 to about 0.2 throughout the full dense-phase reaction zone. When used for catalytic cracking of hydrocarbon oils, particularly heavy feedstock oils, the process, reactor and system show a high contact efficiency between oil and catalyst, a selectivity of the catalytic reaction, an effectively reduced yield of dry gas and coke, and an improved yield of high value-added products such as ethylene and propylene.

The present disclosure relates to an FCC catalyst composition and a process for preparing the same. In a first aspect, there is provided an FCC catalyst composition comprising 25 to 45 wt % Y-type zeolite, 20 to 40 wt % silicon oxide, 5 to 25 wt % alumina, 5 to 35 wt % of at least one clay and 0.5 to 3 wt % of at least one rare earth oxide. The weight % of each of the component is with respect to the total weight of the composition. The FCC catalyst composition has an average particle size in the range of 45-120μ. In a second aspect, there is provided a process for preparing the FCC catalyst composition, which uses ball milled pseudoboehmite having an average particle size in the range of 1 to 8 micron and the whole process is carried out at a pH value in the range of 6 to 7.

A composition of fuel gas that when mixed with spent catalyst and oxygen has an induction time that allows bubbles to break up while combusting in the regenerator. Bubble breakage in a dense bed avoids generation of a flame that can generate hot spots in the regenerator which can damage equipment and catalyst. The fuel gas can be obtained from paraffin dehydrogenation products, so it can sustain operation of the unit even in remote locations. Heavier streams can be mixed with lighter streams to obtain a fuel gas composition with a desirable induction time to avoid such hot spots. Mixing of a depropanizer bottom stream and/or deethanizer overhead stream with lighter gas streams such as cold box light gas or PSA tail gas can provide the desired fuel gas composition.

This invention provides a catalyst composition characterized in that the catalyst composition comprises one or more rare earth oxophosphorus components.

This invention provides a catalyst composition characterized in that the catalyst composition comprises one or more rare earth oxophosphorus components.

An addition system for introducing particulate material into an industrial process is disclosed. The addition system comprises a vessel for holding the particulate material, wherein the vessel has a top and a bottom; one or more weighing devices; a controller for controlling operation of the addition system; a base plate to support the vessel and optionally the controller; and three or more legs, each leg having an uppermost section that connects to the vessel and a foot that is connected to the base plate. The widest diameter of the vessel is less than the diameter of a circle drawn through the feet of the legs. The one or more weighing device are mounted on the base plate and support the legs of the vessel.

A method of depolymerizing polymeric material including the steps of: (a) feeding a polymeric material to a depolymerization reactor maintained at a temperature in the range of from 400° C. to 600° C. and operated under a pressure in the range of from 4 to 15 barg; and (b) depolymerizing at least a portion of the polymeric material thereby forming a first gaseous product and a first liquid product.

A process for recovering catalyst from a fluidized catalytic reactor effluent is disclosed comprising reacting a reactant stream by contact with a stream of fluidized catalyst to provide a vaporous reactor effluent stream comprising catalyst and products. The vaporous reactor effluent stream is contacted with a liquid coolant stream to cool it and transfer the catalyst into the liquid coolant stream. A catalyst lean vaporous reactor effluent stream is separated from a catalyst rich liquid coolant stream. A return catalyst stream is separated from the catalyst rich liquid coolant stream to provide a catalyst lean liquid coolant stream, and the return catalyst stream is transported back to said reacting step.

The invention is directed to a process to prepare propylene from a mixture of hydrocarbons having an olefin content of between 5 and 50 wt. % and boiling for more than 90 vol. % between 35 and 280 ?C or from a hydrocarbon feed comprising paraffins, naphthenics and/or aromatics and optionally up to 10 wt. % of olefins, by first contacting the feed with a low acidic density cracking catalyst in a reactor, separating propylene and subsequently contacting the residue with a high acidic density cracking catalyst in a reactor at a more elevated temperature, separating propylene and recycling the residue to first and second cracking reactors. Aromatics may be added to first and second cracking step to improve cycle length.