| abstract |
A catalytic process is provided for the ethylation of a mono alkyl benzene wherein the alkyl substituent contains 1 or 2 carbon atoms, i.e. toluene or ethylbenzene, to selectively produce the para and meta derivatives of said mono alkyl benzene to the exclusion or substantial exclusion of the ortho derivative thereof by contacting said mono alkyl benzene, under conversion conditions, with an ethylating agent in the presence of a catalyst comprising a crystalline aluminosilicate zeolite, which zeolite is characterized by an activity, in terms of alpha value, of between about 2 and about 5000, and preferably between about 20 and about 500, a xylene sorption capacity greater than 1 gram/100 grams of zeolite and an ortho xylene sorption time for 30 percent of said capacity of greater than 10 minutes, said sorption capacity and sorption time being measured at 120 DEG C. and a xylene pressure of 4.5 +/- 0.8 mm. of mercury, said crystalline aluminosilicate zeolite being further characterized by having a silica to alumina ratio of at least about 12 and a constraint index, as hereinafter defined, within the approximate range of 1 to 12, said catalyst having been subjected to steam treatment at a temperature between about 250 and about 1000 DEG C. for a period of between about 0.5 and about 100 hours. |