Catalytic composition and process using it for the alkylation of aromatic hydrocarbons with alcohols, or mixtures of alcohols and olefins

20:

• The composition according to claim 19, wherein the total weight of alkaline metal ions is lower than or equal to 0.015%

21:

• The composition according to claim 19, wherein the zeolite is ZSM-12.

22:

• The composition according to claim 19, containing sodium in an amount ranging from 5 to 40 ppm and potassium in an amount ranging from 5 to 80 ppm.

23:

• The composition according to claim 19, containing a binder.

24:

• The composition according to claim 19, comprising a MTW zeolite in acid form wherein the cationic sites present in its structure are occupied by Na+ and K+ ions and the remaining cationic sites are occupied by H+ ions.

25:

• The composition according to claim 24, wherein the zeolite is a ZSM-12 zeolite, having, in its calcined and anhydrous form, a molar composition of the oxides corresponding to the following formula:
• 1.0±0.4 M2O.Al2O3.20-500 SiO2.zH2O,
• wherein z ranges from 0 to 60, M is H+ and Na+ and K+ ions, in a total amount lower than 0.02% by weight with respect to the total weight of the catalytic composition.

26:

• The composition according to claim 23, in the form of a pellet having a diameter ranging from 1.5 to 5 mm and a length ranging from 1 to 50 mm, with a hardness higher than or equal to 8 kg.

27:

• The composition according to claim 23, having an extrazeolitic porosity not lower than 0.4 ml/g, wherein said extrazeolitic porosity is for at least 30% characterized by pores having a diameter greater than 100 Å.

28:

• A process for the alkylation of aromatic hydrocarbons with alcohols, or mixtures of the alcohol used and corresponding olefin, which comprises effecting said alkylation reaction in the presence of a catalyst, according to claim 19.

29:

• The process according to claim 28, wherein the aromatic hydrocarbon is benzene or toluene.

30:

• The process according to claim 28, wherein the alcohol is an aliphatic alcohol containing from 1 to 8 carbon atoms.

31:

• The process according to claim 30, wherein the alcohol is ethanol or iso-propanol.

32:

• The process according to claim 28, wherein the alcohol is used in mixture with the corresponding olefin.

33:

• The process according to claim 28, carried out in gas phase, mixed phase or liquid phase.

34:

• The process according to claim 33, carried out under reaction conditions corresponding to a complete gas phase of the reagents.

35:

• The process according to claim 28, carried out under trickle-flow conditions.