A device for treating fluid mixtures, which contain gases, such as hydrogen (H2), air, nitrogen (N2), or natural gases, and liquids, such as ionic liquids, hydraulic fluid, or process liquids, has a first separation stage (29) for separating the fluid mixture into a liquid fraction and a gas fraction contaminated with a remaining liquid fraction. From the gas fraction, the remaining liquid fraction is removed in at least one further separation stage (67).