GB742966A - Improvements in and relating to catalytic reforming of gasolines - Google Patents

Abstract

A process for the catalytic reforming of gasolines containing less than 35 per cent by weight of naphthenes comprises conducting the gasoline in a first stage over a platinum catalyst on a carrier consisting of or containing aluminium oxide, together with at least 500 litres of hydrogen per Kg. of the gasoline, at a pressure of at least 20 atmospheres at 470-530 DEG C., separating a fraction boiling within the boiling range of gasoline and passing this fraction together with not more than 500 litres of hydrogen per Kg, the amount of hydrogen employed being such that the molar ratio of the hydrogen present to the hydrocarbons is less than 3 : 1 over a regenerable cyclization catalyst comprising a metal or a compound of a metal of Group 5, 6 or 8 of the Periodic Classification, under a pressure of not more than 20 atmospheres at 490-550 DEG C. and at a rate of not more than 2 Kg. of said fraction per litre of catalyst per hour. In an example, a gasoline fraction boiling at 121-196 DEG C. having an aromatic content of 17 per cent by weight, and a naphthenes content of 27 per cent by weight was fed at 2 Kgs. per litre of catalyst per hour in the presence of 1500 litres of a gas mixture which contains 83 per cent by volume of hydrogen, per Kg. of the gasoline, over a commercial platform catalyst at 50 atmospheres at 485 DEG C. A fraction consisting of pentane and higher boiling hydrocarbons and having an octane number of 71 was passed with 100 litres of hydrogen per Kg. over a Cr2O3-Al2O3 catalyst under 5 atmospheres at 520 DEG C. The resulting reformate had an octane number of 80. The regenerable catalyst may be of the molybdenum oxide, chromium oxide and platinum types.