Abstract A process for manufacturing high octane gasoline from a low octane paraffinic naphtha, which comprises hydrocracking a first portion of the naphtha to yield a C4 fraction comprising isobutane and a hydrocracked light naphtha fraction having a relatively high octane number, catalytically cracking a second portion of the naphtha to yield a C3-C4 fraction comprising propylene, butylenes and isobutane and a catalytically cracked light naphtha fraction having a relatively high octane number, and reacting, in an alkylation zone the hydrocracked C4 fraction and the catalytically cracked C3-C4 fraction to yield a high octane gasoline alkylate. The proportion of naphtha charged to the hydrocracking zone and the catalytic cracking zone are adjusted such that isobutane, butylene and propylene charge to the alkylation zone are in stoichiometric balance.
The process of claim 1 wherein the hydrocracked C4 fraction and the cracked C3-C4 fraction charged to an alkylation process yield high octane C7-C8 alkylated hydrocarbons suitable for use as gasoline blend stocks.
Claim 2
Dependent Claim
49 words
The process of claim 2 wherein the ratio of raffinate charged to the hydrocracking process and raffinate charged to the fluid catalytic cracking process is maintained such that the combined hydrocracked C4 fraction and cracked C3-C4 fraction contains isobutane in about an equal molar ratio to propylene and butylenes.
Claim 3
Dependent Claim
51 words
The method of claim 1 wherein the raffinate boils in the range of about C5 to about 400*F., wherein a hydrocracked heavy naphtha fraction boiling above 250*F. is recovered from the hydrocracking reaction, and wherein a cracked heavy naphtha fraction boiling above 250*F. is recovered from the fluid catalytic cracking reaction.
Claim 4
Dependent Claim
100 words
The method of claim 4 wherein the hydrocracked heavy naphtha fraction and the cracked heavy naphtha fraction are charged as feed stock to a catalytic reforming reaction, wherein a reformed hydrocarbon fraction boiling in the range of from about C5 to about 400*F. comprising aromatic hydrocarbons and paraffinic hydrocarbons recovered from the catalytic reforming reaction, is solvent extracted to yield a raffinate fraction comprising paraffinic hydrocarbons and an aromatic fraction, wherein the raffinate fraction is employed as charge stock to the hydrocracking and fluid catalytic cracking reactions, and wherein the aromatic hydrocarbon fraction is recovered from the solvent extraction zone.
Claim 5
Dependent Claim
38 words
The method of claim 4 wherein the hydrocracked heavy naphtha fraction is recycled to extinction within the hydrocracking reaction zone, and wherein the cracked heavy naphtha fraction is recycled to extinction within the fluid catalytic cracking reaction zone.
Claim 6
Dependent Claim
35 words
The method of claim 5 wherein fresh feed in addition to raffinate is charged to the hydrocracking zone and wherein fresh feed in addition to the raffinate is charged to the fluid catalytic cracking zone.