A container ( 1 ) having a first compartment ( 3 ) and a second compartment ( 5 ) separated by a movable gas impermeable partition ( 7 ) is used for storing and dispensing a gas for use in a process and receiving and storing a gas recovered from the process. Fresh gas is dispensed ( 9 ) from the first compartment ( 3 ) for use in a process and recovered gas is fed ( 11 ) to the second compartment ( 5 ), whereby a volume of the second gas displaces a volume of the first gas by movement of the partition ( 7 ) to enlarge the second compartment ( 5 ) relative to the first compartment ( 3 ).