The invention relates to a system and to a method for separating into at least one of liquid and gas phase compounds contained in a sample. The system comprises: an oven (D1) for heating in an inert atmosphere according to a sequence of temperatures, a first experimental setup (M1) connected to oven (D1) when it is in operation, comprising circulating the effluent resulting from heating in an inert atmosphere towards collection of (U) this effluent, a second experimental setup (M2) connected to first experimental setup (M1) when the oven is no longer in operation, comprising vacuum circulation (PI, P.G., TP) of the effluent collected by the first setup towards (T1, T2) which separate the collected effluent into at least one of liquid and gas phases.