Preparation of alkylbenzenes

Claim 1

A PROCESS FOR PREPARING 1,2,3-TRIALKYLBENZENES AND 1,2,3,4-TETRAALKYLBENZENES WHOSE ALKYL SUBSTITUENTS CONTAIN LESS THAN 4 CARBON ATOMS PER SUBSTITUENT WHICH PORCESS COMPRISES ALKYLATING AT LEAST ONE POLYALKYLBENZENE FEEDSTOCK SELECTED FROM THE GROUP CONSISTING OF 1,2-DIALKYLBENZENES, 1,3-DIALKYLBENZENES AND 1,2,4-TRIALKYLBENZENES WHOSE ALKYL SUBSTITUENTS CONTAIN LESS THAN 4 CARBON ATOMS PER SUBSTITUENT WITH AN ALKYLATING AGENT HAVING AT LEAST ONE TERTIARY CARBON ATOM PER MOLECULE AND THEREBY FORMING A MONO-TERTIARY ALKYL-SUBSTITUTED POLYALKYLBENZENE, CONDENSING THE MONO-ALKYLATED POLYALKYLBENZENE WITH AN ALDEHYDE CONTAINING FROM 1 TO 3 CARBON ATOMS PER MOLECULE AND FORMING AN ALKYL-SUBSTITUTED DIARYLALKANE, SUBJECTING THE DIARYLALKANE TO CRACKING CONDITIONS WHICH EFFECT NO SUBSTANTIAL ISOMERIZATION OF THE ALKYL SUBSTITUENTS WHEREBY THE TERTIARY ALKYL SUBSTITUENTS ARE REMOVED AND THE DIARYLALKANE IS SPLIT INTO TWO POLYALKYLBENZENE MOLECULES, ONE OF WHICH MOLECULES IS IDENTICAL WITH THE FEED POLYALKYLBENZENE AND THE OTHER POLYALKYLBENZENE MOLECULE HAVING ONE MORE ALKYL SUBSTITUENT THAN WAS CONTAINED IN THE FEED POLYALKYBENZENE AND WHICH ADDITIONAL SUBSTITUENT HAS THE SAME NUMBER OF CARBON ATOM AS THE ALDEHYDE, AND THEREBY FORMING 1,2,3-TRIALKYLBENZENES FROM 1,2- AND 1,3-DIALKYLBENZENES AND FORMING 1,2,3,4-TETRAALKYLBENZENES FROM 1,2,4-TRIALKYLBENZENES.