Chlorine regeneration of platinum group metal zeolite catalysts

Claim 1

A process for the regeneration of a catalyst consisting essentially of an acid-resistant alkali-metal deficient mordenite containing a platinum group metal hydrogenating component within its pores, which has become deactivated during the selective hydrocracking of n-paraffins in a waxy hydrocarbon feedstock, comprising the steps of a. burning off carbonaceous deposits on the catalyst with a stream of inert gas and oxygen at a temperature controlled to a maximum of 550° C, the water content of the gas at the inlet being below 200 ppm volume, b. treating the catalyst at 400° - 550° C, with a stream of inlet gases comprising an inert gas, from 0.5 to 20% volume of free oxygen and from 5 to 500 ppm vol. of chlorine, the water content of the inlet gases having an inlet water content of below 200 ppm volume, until the catalyst has been treated with 0.1 to 5% by weight of chlorine based on the weight of the catalyst, the chlorine for reaction being provided by a chlorine-containing material selected from the group consisting of chlorine gas, HCl and a chlorinated derivative of a C 1 -C 4 hydrocarbon, c. purging the catalyst to remove residual oxygen and chlorine, d. reducing the catalyst in a stream of hydrogen at 200° - 600° C and wherein in steps (a), (b), (c), and (d) the gas streams flow at a gas mass velocity of at least 500 Kg/m 2 of catalyst bed cross section/hr.