Various embodiments include a system for carbon dioxide electrolysis comprising: an anode and a cathode both connected to a voltage supply, wherein the cathode comprises a gas diffusion electrode adjoined by a gas space and a cathode space; an electrolyte circuit; a gas supply delivering carbon dioxide to the gas space; wherein the gas space has an outlet for an electrolyte, carbon dioxide, and product gases produced by electrolysis; a return connection connecting the outlet to the gas supply; and a pump for circulation of carbon dioxide and product gas in the gas space and the return connection.