MULTI-STAGE FRACTIONATION OF FCC NAPHTHA WITH POST TREATMENT AND RECOVERY OF AROMATICS AND GASOLINE FRACTIONS

• Main Author: ALSHAREEF ALI H
• Format: Patent
• Language: Chinese; English
• Published: 23.07.2021
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; CRACKING HYDROCARBON OILS; FUELS; LUBRICANTS; METALLURGY; MINERAL WAXES; ORGANIC CHEMISTRY; PEAT; PETROLEUM, GAS OR COKE INDUSTRIES; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVEHYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, ORGASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; TECHNICAL GASES CONTAINING CARBON MONOXIDE

A stream of cracked naphtha is fractionated into at least four specified fractions defined by their respective boiling point ranges. The lightest fraction, IBP to 50 DEG C, is treated in a selective etherification or alkylation process to reduce its RVP value and increase its RON. The second fraction, 50 DEG C to 150 DEG C, is selectively hydrogenated to treat and convert the diolefins present and the treated stream is sent directly to the gasoline blending pool since it has the desired RON and low sulfur content. The third, and optionally a fourth fraction, boiling in the range of 50 DEG to 180 DEG C, in an embodiment, are utilized for the production of aromatics and the raffinate stream, after aromatic extraction, is sent to the gasoline blending pool. A fraction of this latter stream can optionally be recycled for further cracking to produce additional aromatics and gasoline blending components. The heaviest fraction, 180 DEG C to MBP, constitutes a relatively small volume and is hydrotreated at high press