Process for the preparation of hydrocarbons

Abstract

The present invention describes a process for the conversion of a lower alkane or a mixture of lower alkanes or a feed containing lower alkane(s) to aromatics or higher hydrocarbons, which comprises (i) treating a bifunctional pentasil zeolite catalyst, optionally containing one or more transition elements, having strong dehydrogenation and acid sites with a mixture of H.sub.2, steam and optionally the presence of an inert gas at a gas hourly space velocity of at least about 500 cm.sup.3 g.sup.-1 h.sup.-1 at a temperature in the range of 400.degree.-800.degree. C. and pressure in the range of 1-5 atm. for a period of at least 0.5 h; (ii) treating the catalyst obtained in step (i) with air or O.sub.2 at a gas hourly space velocity of at least about 200 cm.sup.3 g.sup.-1 h.sup.-1) at a temperature in the range of 400-800.degree. C. and pressure in the range of 1-5 atm for a period of at least 0.2 h, and (iii) contacting the catalyst obtained in step (ii) with a lower alkane or mixture of lower alkanes and at least one olefin or at least one higher paraffin or both, at a gas hourly space velocity in the range of 1000-100000 cm.sup.3 g.sup.-1 h.sup.-1 at a temperature in the range of 300.degree.-600.degree. C. and pressure in the range of 1-5 atm, (iv) separating the aromatics formed from the reaction mixture by known methods and if desired, (v) recycling the unconverted lower alkanes and non-aromatics to step (iii) for further conversion.

Dependencies are inferred from the claim text.