A process for liquefying a hydrogen process gas comprising: introducing a hydrogen heat transfer fluid into an active magnetic regenerative refrigerator apparatus that comprises (i) a high magnetic field section in which the hydrogen heat transfer fluid flows from a cold side to a hot side through at least one magnetized bed of at least one magnetic refrigerant, (ii) a first no heat transfer fluid flow section in which the bed is demagnetized, (iii) a low magnetic field or demagnetized section in which the hydrogen heat transfer fluid flows from a hot side to a cold side through the demagnetized bed, and (iv) a second no heat transfer fluid flow section in which the bed is magnetized; continuously introducing the hydrogen heat transfer fluid from the cold side of the low magnetic field or demagnetized section into the cold side of the high magnetic field section; continuously diverting a portion of the hydrogen heat transfer fluid flowing from the cold side of the low magnetic field or demagnetized section into an expander; and isenthalpically expanding the diverted portion of the hydrogen heat transfer fluid to produce liquefied hydrogen.