Methods and systems for treating pygas are disclosed. Methods include depentanizing the pygas to produce a C.sub.5 stream and a C.sub.6+ stream before hydrotreating the C.sub.6+ stream, to integrate the processing of pygas with the production of isoprene, piperylene, and dicyclopentadiene. Systems include a depentanizer added before a pygas hydrotreatment unit.

The present invention is based on the use of a two-step hydrocracking process for the production of naphtha, comprising a step of hydrogenation placed upstream of the second hydrocracking step, the hydrogenation step treating the unconverted liquid fraction separated in the distillation step in the presence of a specific hydrogenation catalyst. Furthermore, the hydrogenation step and a second hydrocracking step are carried out under specific operating conditions and in particular under temperature conditions that are very specific with respect to one another.

A catalytic conversion process for producing gasoline and propylene includes the steps of 1) subjecting a feedstock oil to a first catalytic conversion reaction in a first catalytic conversion reaction device to obtain a first reaction product; 2) separating the first reaction product to obtain a propylene fraction, a gasoline fraction and a fraction comprising C.sub.4 olefin; 3) carrying out an oligomerization reaction on the fraction comprising C.sub.4 olefin in an oligomerization reactor to obtain an oligomerization product comprising C.sub.12 olefin, and optionally separating the oligomerization product to obtain a fraction comprising C.sub.12 olefin; 4) recycling the C.sub.12 olefin-containing oligomerization product or fraction to the first catalytic conversion reaction device, and/or sending the C.sub.12 olefin-containing oligomerization product or fraction to a second catalytic conversion reaction device for a second catalytic conversion reaction to obtain a second reaction product comprising propylene.

A process for facile separation of lighter hydrocarbon fractions from the heavier fractions of hydrocarbon oil feedstocks is disclosed, which utilizes novel sparging and reverse distillation techniques. The present invention can be utilized for the facile topping of crude oil extracted on-site. Moreover, while heavier hydrocarbon fractions may be shipped to refineries for further processing, this invention will also prove useful for quick separation of light fractions produced by cracking processes off-site.

The present invention relates to a method for obtaining a fraction oil yield from petroleum hydrocarbons in a distillation column, wherein said distillation column comprises a fractionation stage, a vaporization section and a stripping stage from the top to the bottom of the distillation column. The method comprises preheating and sending a feedstock oil of petroleum hydrocarbons through a pressure-feeding system at a pressure of 100-1000 kPa higher than the vaporization section pressure of the distillation column, wherein said preheating is conducted in a heating furnace, wherein said heating furnace has an outlet pressure of 100-1000 kPa higher than the vaporization section absolute pressure, and an outlet temperature of 360-460 C.

System and method for producing olefins are disclosed. The method includes using a radial flow moving bed reactor system to catalytically crack paraffins, in multiple stages with continuous catalyst regeneration, to form olefins. The system includes inter-stage heaters to facilitate increase in yield of olefins.

Assemblies and methods to enhance control of a fluid catalytic cracking (FCC) processing assembly associated with a refining operation, may include supplying a hydrocarbon feedstock to one or more first processing units associated with the refining operation. The assemblies and methods also may include conditioning a hydrocarbon feedstock and unit material samples, and analyzing the samples via one or more spectroscopic analyzers. The assemblies and methods further may include prescriptively controlling, via one or more FCC process controllers based at least in part on the hydrocarbon feedstock properties and the unit material properties, the FCC processing assembly, so that the prescriptively controlling results in enhancing accuracy of target content of materials produced by the FCC processing assembly, thereby to more responsively control the FCC processing assembly to achieve material outputs that more accurately and responsively converge on target properties.

Disclosed is a method for maximizing ethylene or propene production, the main steps thereof being: taking crude oil and distillate thereof, pre-processing urban mixed-waste plastics as raw material, then entering same into a catalytic cracking reactor, removing via a two-stage pre-wash tower and related separation, then cooling the reacted high-temperature oil and gas and removing impurities to obtain light and heavy distillate oils; performing a hydrogenation reaction operation on the heavy distillate oil; performing light distillate oil separation, performing a recombination operation on its olefins, its alkanes entering a steam cracking apparatus to produce rich ethylene, and its aromatic components being separated as by-products; the product of the described hydrogenation and recombination reaction and the steam-cracked distillate oil is recycled to the catalytic cracking reactor. In the production method of the present invention, the yield of ethylene and propene together is 45-75 m % of the raw material, and the yield of aromatics is 15-30 m % of the raw material; in particular, when using urban mixed-waste plastics as raw material, the ethylene or propene thus produced are used to produce new plastics by way of a conventional polymerization process, achieving the chemical recycling of waste plastics.

A process for upgrading a hydrocarbon feed includes contacting the hydrocarbon feed with steam in the presence of a cracking catalyst at reaction conditions sufficient to cause at least a portion of hydrocarbons in the hydrocarbon feed to undergo one or more cracking reactions to produce a steam catalytic cracking effluent comprising light olefins, light aromatic compounds, or both. The cracking catalyst is hierarchical mesoporous ZSM-5 zeolite. The hierarchical mesoporous ZSM-5 zeolite is made by providing a starting ZSM-5 zeolite, disintegrating the a portion of the starting ZSM-5 in the presence of a surfactant using sodium hydroxide, and then recrystallizing the zeolite constituents in the presence of the surfactant to produce recrystallized ZSM-5 zeolite. The recrystallized ZSM-5 zeolite is then recovered and calcined to produce the hierarchical mesoporous ZSM-5 zeolite.

Methods and systems are provided herein utilizing a membrane cascade to separate a hydrocarbon feed into boiling point fractions. Also provided herein are methods for selecting membranes for said cascades to achieve the desired boiling point fraction separation.