Process for producing paraethyltoluene

Claim 1

A PROCESS FOR THE PREPARATION OF AN ETHYL TOLUENE PRODUCT FRACTION BEING A MIXTURE OF ETHYL TOLUENE ISOMERS HAVING A PARA-ISOMER CONTENT OF AT LEAST 30% FROM ETHYLENE AND TOLUENE INCLUDING THE STEPS OF ALKYLATING, DISPROPORTIONATING AND ISOMERIZING WHICH COMPRISES THE STEPS OF (A) ALKYLATING TOLUENE WITH AN AMOUNT OF ETHYLENE TO PROVIDE IN THE REACTION MIXTURE A MOL RATION OF ALKYL GROUPS TO BENZENE RING OF 1.4 TO 2.1, IN THE PRESENCE OF ALUMUNUM CHLORIDE AND AT A TEMPERATURE IN THE RANGE OF FROM 50 TO 90*C., (B) FRANCTIONATING IN THE DROCARBON MIXTURE PRODUCED BY SAID ALKYLATION TO OBTAIN A TOLUENE FRACTION, AN ETHYL TOLUENE FRACTION AND A DIETHYL TOLUENE FRACTION, (C) DISPROPORTIONATING THE DIETHYL TOLUENE FROM STEP (B) AND DIETHYL TOLUENE FRACTION HEREINAFTER DERIVED BY REACTION WITH TOLUENE FRACTION FROM STGEP (B) AND TOLUENE FRACTIONS HEREINAFTER DERIVED, IN THE PRESENCE OF ALUMINUM CHLORIDE AT A TEMPERATURE NOT ABOVE 90*C., (D) FRACTIONATING THE HYDROCARBON MIXTURE PRODUCED BY STEP (C) TO SEPARATE A TOLUENE FRACTION, AN ETHYL TOLUENE FRACTION AND DIETHYL TOLUENE FRACTION, (E) FRACTIONATING THE COMBINED ETHYL TOLUENE FRACTIONS OBTAINED FROM STEPS (B) AND (D) AND HEREINAFTER DERIVED FROM THE ISOMERIZATION STEP TO OBTAIN AS PRODUCT AN OVERHEAD ETHYL TOLUENE FRACTION CONTAINING AT LEAST 30 PERCENT PARA-ISOMER AND A BOTTOM FRACTION RICH IN ORTHO-ISOMER, (F) ISOMERIZING SAID ORTHO-ISOMER RICH BOTTOM FRACTION IN THE PRESENCE OF ALUMINUM CHLORIDE AT A TEMPERATURE NOT ABOVE 90*C., AND (G) FRACTIONATING THE HYDROCARBON MIXTURE OBTAINED FROM SAID ISOMERIZATION TO OBTAIN A TOLUENE FRACTION, AN ETHYL TOLUENE FRACTION AND A DIETHYL TOLUENE FRACTION, WHEREIN EACH OF SAID STEPS OF ALKYLATING, DISPROPORTIONATING AND ISOMERIZING THE AMOUNT OF ALUMINUM CHLORIDE IS IN THE RANGE OF 0.5 TO 3. PERCENT BY WEIGHT BASED ON THE HYDROCARBON PRESENT.