Enhanced storage of hydrogen at the temperature of liquid nitrogen

Storage of hydrogen in activated carbon at liquid nitrogen temperature is considerably enhanced in terms of compression and adsorption on activated carbon. To reach the capacity of 4.1 kg per 100 1 of storage vessel, it needs to compress the gas to as high a pressure as 75 MPa at 298 K, but only to 15 MPa if compressed at 77 K. The pressure is reduced to 6 MPa if the container is filled with pellets of activated carbon AX-21. Liquid nitrogen is cheap in cost and widely available. Therefore, storing hydrogen on activated carbon cooled by liquid nitrogen seems feasible for the hydrogen vehicle programs. (C) 2003 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.