Cracking hydrocarbon residua

Abstract

Abstract HYDROCARBON RESIDUA BOILING MOSTLY 1000* F. AND ABOVE ARE DEPOLYMERIZED IN THE PRESENCE OR ABSENCE OF HYDROGEN IN ONE OR MORE STAGES UNDER LIQUID PHASE CONDITIONS TO OBTAIN A PRODUCT WHICH IS PREDOMINANTLY AN AROMATIC GAS OIL AND EMINENTLY SUITABLE EITHER AS A SOLVENT OR AS FEED TO HYDROCRACKING OPERATIONS. ALTHOUGH THE UPPER BOILING LIMIT OF THIS GAS OIL MAY BE IN THE RANGE OF 600 TO 1000*F., THE PROCESS IS ILLUSTRATED BY TWO SCHEMES, ONE IN WHICH THE GAS OIL IS SEPARATED INTO FRACTIONS BOILING 430-650*F., 650-1000*F. AND 1000*F.+ AND THE OTHER IN WHICH THE GAS OIL IS SEPARATED INTO 430-650*F. AND 650*F.+ FRACTIONS. IN EACH SCHEME AN AMOUNT OF THE LOWBOILING FRACTION IS RECYCLED SO THAT THE FEED MIXTURE TO THE REACTION ZONE CONTAINS 20 TO 50% OF THE LOW-BOILING FRACTION WHILE THE HIGH BOILING FRACTION IS RECYCLED AT A RATE SUCH THAT THE AMOUNT PRESENT IN THE FEED MIXTURE TO THE REACTOR IS EQUAL TO THE AMOUNT IN THE MAKE PRODUCT THUS RESULTING IN BALANCED CONDITIONS. 1-25% OF AN ACYCLIC HYDROCARBON MODIFIER AND/OR A MILD ALKALI IS ADDED TO THE REACTION MIXTURE TO ACT AS A FREE-RADICAL ACCEPTOR. WHEN A HYDROCARBON IS USED IT HAS A RESIDENCE TIME OF ONE HOUR OR LESS AS COMPARED TO 1 TO 6 HOURS FOR THE RESIDUA-RECYCLE MIXTURE.

Inventors

• 👤 Ralph B Mason
• 👤 Glen P Hamner

Bibliographic Details