Continuous process to separate colour bodies and/or asphalthenic contaminants from a hydrocarbon mixture

A continuous process to separate colour bodies and/or asphaltenic contaminants from a hydrocarbon mixture by passing part of the hydrocarbon mixture through a membrane over which membrane a pressure difference is maintained thereby obtaining a hydrocarbon permeate having a reduced content of colour bodies and/or contaminants, wherein at regular time intervals the pressure difference over the membrane is substantially lowered, wherein during the process the pressure difference is maintained at a level of zero (0) or greater, wherein the pressure difference is substantially lowered by stopping the flow to the membrane.