Process for the regeneration of an at least partially coked molecular sieve catalyst comprising introducing the at least partially coked catalyst into a regenerator; introducing into the regenerator an oxygen-containing gas to regenerate at least part of the at least partially coked catalyst, thereby producing a gaseous mixture and at least partially regenerated catalyst; recovering part of the at least partially regenerated catalyst; analysing the at least partially regenerated catalyst to control the burning rate of the coke present on the at least partially coked catalyst in the regenerator by adjusting one or more conditions of the regeneration of the at least partially coked catalyst on the basis of the analysis of the at least partially regenerated catalyst; and separating at least partially regenerated catalyst and at least part of the gaseous mixture as obtained in step (b).