The invention concerns a process and a facility for reducing the concentration of heavy polycyclic aromatic compounds (HPNA) in the recycle loop of hydrocracking units, which comprises a fractionation column.

In accordance with this process, a portion of the stream present at the level of at least one plate located between the plate for supplying hydrocracked effluent and the plate for withdrawing the distillate fraction which is the heaviest is withdrawn from the fractionation column and at least a portion of said withdrawn stream is recycled to the column directly or after optional liquid separation, and optionally a portion of said withdrawn stream is recycled to the hydrocracking step directly or after optional gas separation.

Systems and methods are provided for processing of challenged feedstocks to produce distillate fuel products, such as jet boiling range products and/or diesel boiling range products. The challenged feedstocks can have a high aromatics content, a low API gravity, and/or a low cetane index/cetane number. A feedstock can be processed to form distillate fuel products by processing the feedstock in reaction system including at least two stages. The first stage can perform an initial amount of hydrotreating and/or hydrocracking, while the second stage can include exposing a portion of the hydrotreated and/or hydrocracked effluent to a USY catalyst including a supported noble metal. The USY catalyst can have a desirable combination of catalyst properties. Processing a challenged feedstock in a second stage with the USY catalyst having a desirable combination of properties can allow for production of an increased yield of distillate fuel from the challenged feedstock.

The invention provides a process to purify a gas stream by using an adsorbent bed and a secondary device to remove heavy hydrocarbons with a recycle stream then sent first to a vessel containing an amine solvent to remove acid gases including carbon dioxide and hydrogen sulfide and then in most embodiments of the invention sending the treated gas stream to a dehydration unit such as an adsorbent bed or to a triethylene glycol absorbent to remove water. The invention further provides improved integration of the process streams to allow for smaller amine solvent and dehydration units as compared to the prior art.

This invention relates to an alkylating process for alkyl benzenes, including the steps of: a) an alkyl benzene and a first stream of alkylating agent being fed into a first reaction zone, contacting with a catalyst A, to produce a process stream I; b) the process stream I and a second stream of alkylating agent being fed into at least one second reaction zone, contacting with a catalyst B, to produce a process stream II; and c) the process stream II being fed into at least one third reaction zone, contacting with a catalyst C, to produce a process stream III containing an alkylate. The present alkylating process can improve the utilization efficiency of the alkylating agent.

Disclosed are a catalyst system and its use in a process for the conversion of a feedstock containing C.sub.8+ aromatic hydrocarbons to produce light aromatic products, comprising benzene, toluene and xylene. The catalyst system comprises (a) a first catalyst bed comprising a first catalyst composition, said first catalyst composition comprising a zeolite having a constraint index of 3 to 12 combined (i) optionally with at least one first metal of Group 10 of the IUPAC Periodic Table, and (ii) optionally with at least one second metal of Group 11 to 15 of the IUPAC Periodic Table; and (b) a second catalyst bed comprising a second catalyst composition, said second catalyst composition comprising (i) a meso-mordenite zeolite, combined (ii) optionally with at least one first metal of Group 10 of the IUPAC Periodic Table, and (iii) optionally with at least one second metal of Group 11 to 15 of the IUPAC Periodic Table, wherein said meso-mordenite zeolite is synthesized from TEA or MTEA and having a mesopore surface area of greater than 30 m.sup.2/g and said meso-mordenite zeolite comprises agglomerates composed of primary crystallites, wherein said primary crystallites have an average primary crystal size as measured by TEM of less than 80 nm and an aspect ratio of less than 2.

The present invention relates to a process for the production of propylene-based polymers from waste plastics feedstocks comprising the steps in this order of: (a) providing a hydrocarbon stream A obtained by treatment of a waste plastics feedstock; (b) providing a hydrocarbon stream B; (c) supplying a feed C comprising a fraction of the hydrocarbon stream A and a fraction of the hydrocarbon stream B to a thermal cracker furnace comprising cracking coil(s); (d) performing a thermal cracking operation in the presence of steam to obtain a cracked hydrocarbon stream D; (e) supplying the cracked hydrocarbon stream D to a separation unit; (f) performing a separation operation in the separation unit to obtain a product stream E comprising propylene; (g) supplying the product stream E to a polymerisation reactor; and (h) performing a polymerisation reaction in the polymerisation reactor to obtain an propylene-based polymer; wherein in step (d): •⋅ the coil outlet temperature is 2:: 800 and:::; 850° C., preferably 2:: 805 and:::; 835° C.; and •⋅ the weight ratio of steam to feed C is >0.3 and <0.8.

A process and system for the production of at least one xylene isomer is provided. The process includes passing a first stream to one side of a split shell fractionation column and a second stream to the other side of the column. The first stream has a higher ratio of methyl to C2+ alkyl-substituted C9 aromatic compounds than the second stream. A bottoms stream from the one side is separated and passed as feed to a transalkylation zone.

Disclosed is a catalytic cracking process for producing isobutane and/or light aromatics in high yield, comprising the steps of: a) providing a catalytic cracking feedstock oil having a polycyclic naphthene content of greater than about 25 wt %; b) subjecting the catalytic cracking feedstock oil to a first catalytic cracking reaction and a second catalytic cracking reaction sequentially under different reaction conditions to obtain a catalytic cracking product; c) separating the resulting catalytic cracking product to obtain a liquefied gas fraction comprising isobutane and a gasoline fraction comprising light aromatics; and d) optionally, recovering isobutane from the liquefied gas fraction and/or recovering light aromatics from the gasoline fraction. The process can enable the production of isobutane and/or light aromatics in high yield.

System relating to the conversion of ethanol in a stripper unit of a fluidized catalytic cracking system. An ethanol stream comprising at least 4 volume percent water mixes with a catalyst in the stripper unit under conditions of temperature that favor conversion of the ethanol to hydrocarbons, thereby increasing incorporation of ethanol into liquid transportation fuels without exceeding regulatory limits on fuel vapor pressure. Certain embodiments additionally combine the ethanol stream with a hydrocarbon stream in the stripper and react in the presence of a catalyst to produce hydrocarbons that may have an increased boiling point, increased octane rating, decreased vapor pressure, decreased benzene content, or combinations of these properties.

Embodiments of the disclosure include processes for ring-opening of hydrocarbon species comprising aromatic and cycloparaffinic rings in hydrocarbon feeds to produce ring-opened products. In particular, the process comprises contacting hydrocarbon species comprising aromatic and cycloparaffinic rings with hydrogen in the presence of a ring-opening catalyst comprising a noble metal on a low-acidity crystalline material containing external pockets to facilitate ring-opening of the hydrocarbon species comprising aromatic and cycloparaffinic rings. The processes are useful in the transformation of polynuclear aromatic hydrocarbons (PAHs) to ring-opened products.