Process gas purification and fuel cell system

A module (214 Fig. 5) for separating a product from a mixed stream comprises a mixed stream chamber having inlet and outlet means and defining a first flow path for the mixed stream, a purge/product stream chamber having inlet and outlet means and defining a second flow path for a purge/product stream, the second flow path having a substantially countercurrent direction to that of the first flow path, and a membrane located between the mixed stream chamber and the purge/product stream chamber, the membrane being selectively permeable to the product. There is also disclosed a fuel cell system comprising a burner module (210) for mixing and combusting a fuel and air mixture to produce hydrogen rich fuel stream; a hydrogen fuel cell (250) for producing power/energy using the hydrogen fuel produced by the burner module; a hydrogen purification module (214) between the burner module and the fuel cell for extracting hydrogen fuel from the burner module for use in the fuel cell and that uses a purge gas to enhance purification module performance; hydrogen storage means (254) for storing hydrogen fuel produced by the burner module and not immediately required by the fuel cell; and means for feeding stored hydrogen fuel from the storage means to the fuel cell when the hydrogen requirements of the fuel cell are greater than the amount of hydrogen produced in the burner module.