A process is presented for the management of sulfur on a catalyst. The catalyst is a dehydrogenation catalyst, and sulfur accumulates during the dehydrogenation process. Sulfur compounds are stripped from the spent catalyst and the catalyst is cooled before the regeneration process. The process includes controlling the amount of sulfur that needs to be removed from the catalyst before regeneration.

A process and apparatus for catalytically cracking fresh heavy hydrocarbon feed to produce cracked products is disclosed. A fraction of the cracked products can be obtained to re-crack it in a downer reactor. The downer reactor may produce high selectivity to light olefins. Spent catalyst from both reactors can be regenerated in the same regenerator.

Systems and methods are provided for selective oxidation of CO and/or C.sub.3 hydrocarbonaceous compounds in a reaction environment including hydrocarbons and/or hydrocarbonaceous components. The selective oxidation can be performed by exposing the CO and/or C.sub.3 hydrocarbonaceous compounds to a catalytic metal that is encapsulated in a small pore zeolite. The small pore zeolite containing the encapsulated metal can have a sufficiently small pore size to reduce or minimize the types of hydrocarbons or hydrocarbonaceous compounds that can interact with the encapsulated metal.

Systems and methods are provided for selective oxidation of CO and/or C.sub.3 hydrocarbonaceous compounds in a reaction environment including hydrocarbons and/or hydrocarbonaceous components. The selective oxidation can be performed by exposing the CO and/or C.sub.3 hydrocarbonaceous compounds to a catalytic metal that is encapsulated in a small pore zeolite. The small pore zeolite containing the encapsulated metal can have a sufficiently small pore size to reduce or minimize the types of hydrocarbons or hydrocarbonaceous compounds that can interact with the encapsulated metal.

Biomass is converted into a bio-oil containing stream in a riser reactor containing a cooling media. The cooling media quenches the rapid heat transfer to the biomass during cracking of the biomass in the mixing zone of the riser. By lowering the temperature to which the mixing zone effluent is exposed, production of carbon monoxide and light gases is decreased during thermolysis of the biomass.

A method of catalytically cracking liquid hydrocarbons is disclosed. The method includes the use of one or more radial flow moving bed reactors. The method may include mixing a liquid hydrocarbon stream comprising primarily C5 and C6 hydrocarbons with water or a dry gas to form a feed mixture and flowing the feed mixture into the one or more radial flow moving bed reactors in a manner so that the feed mixture flows radially inward or radially outward through the moving catalyst bed and thereby contacts the catalyst particles under reaction conditions to produce a hydrocarbon stream comprising light olefins (C2 to C4 olefins).

A catalyst and its use for selectively desulfurizing sulfur compounds present in an olefin-containing hydrocarbon feedstock to very low levels with minimal hydrogenation of olefins. The catalyst comprises an inorganic oxide substrate containing a nickel compound, a molybdenum compound and optionally a phosphorus compound, that is overlaid with a molybdenum compound and a cobalt compound. The catalyst is further characterized as having a bimodal pore size distribution with a large portion of its total pore volume contained in pores having a diameter less than 250 angstroms and in pores having a diameter greater than 1000 angstroms.

Biomass is converted into a bio-oil containing stream in a riser reactor containing a cooling media. The cooling media quenches the rapid heat transfer to the biomass during cracking of the biomass in the mixing zone of the riser. By lowering the temperature to which the mixing zone effluent is exposed, production of carbon monoxide and light gases is decreased during thermolysis of the biomass.

Spent zeolite equilibrium catalyst from the fluidized catalytic cracker has a useful function as an adsorbent for jet fuel. Redirecting such spent catalyst saves costs for refinery operations in two ways. The first is by avoiding the costs for disposing of such catalyst as hazardous waste. The second is to reduce the cost of procuring sorbent for the jet fuel decontamination process. Since zeolite is primarily silica and conventional sorbents are also silica, zeolite catalysts are chemically similar. And the equilibrium catalyst may be regenerated in the FCC after its becomes saturated with jet fuel contaminants and re-used.

A fluidized catalytic conversion method for producing light olefins includes the following steps: 1) introducing an olefin-rich feedstock into a fluidized catalytic conversion reactor, and contacting with a catalyst having a temperature of 650 C. or higher for reaction; 2) separating the reaction product vapor obtained by the reaction to obtain a stream comprising C5+ olefins; and 3) recycling at least a part of the stream comprising C5+ olefins to step 1) for further reaction. The fluidized catalytic conversion method can effectively improve the yield of light olefins, improve the selectivity and improve the ethylene/propylene ratio of the product.