Combination process for manufacturing ethylene, benzene and alkylated benzene
OwnerDavid Netzerinventor
Life of this patent
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Abstract
Gas and liquid products of an ethylene plant, steam cracking zone, are used for the coproduction of alkylated benzene. Dilute ethylene in typical concentrations of 7-20 mol percent is coproduced along with pure ethylene product. Impure benzene containing typically less than 8 wt % C6 and C7 non-aromatics is formed by hydratreating and fractionation of pyrolysis gasoline, rich in benzene and toluene, and also by hydrodealkylation of the toluene. The impure benzene reacts with dilute ethylene to form ethylbenzene and hydrogen rich vent gas. The impure benzene can be also a source for production of cumene, by reaction with propylene.
Claims12
A process for the simultaneous coproduction of ethylbenzene and ethylene comprising:
- (1) producing ethylene and a dilute ethylene mixture containing ethylene and methane and no more than 200 mol-ppm propylene via conventional steam cracking in a steam cracker and downstream propylene separation;
- (2) producing an impure benzene mixture by hydrogenation and fractionation of pyrolysis gasoline during the ethylene production, the impure benzene mixture containing benzene and a total of 1.0 to 20.0 wt % of one or more impurities selected from the group consisting of cyclohexane, dimethylpentanes, methylcyclopentanes and methylcyclohexane;
- (3) feeding impure benzene mixture to an integrated ethylbenzene production zone;
- (4) feeding at least a portion of the dilute ethylene mixture produced during the steam cracking and downstream propylene separation to the ethylbenzene production zone, wherein the ethylene is present in the dilute ethylene mixture in a concentration of about 3 to 40 vol %;
- and
- (5) reacting the ethylene in the dilute ethylene mixture with the benzene in the impure benzene mixture to form ethylbenzene.
Dependencies are inferred from the claim text.