Preparation of Activated Carbon with High Surface Area using Biomass Wastes and Its Application to Methane Storage Technology

Methane gas is an alternative fuel to petroleum. However, the two conventional methods of storing methane, as liquefied natural gas (LNG) and compressed natural gas (CNG), involve a high degree of risk in terms of safety. To develop a high-safety and low-cost method of storing methane gas, we examined its adsorption on activated carbons newly prepared from biomass wastes, bamboo and crab shell, by chemical activation with K2CO3. The activated carbons prepared from the mixture of bamboo and crab shell exhibited the maximum specific surface area of 2,654 m(2) g(-1) as measured by the nitrogen gas adsorption method. The adsorption isotherms of methane gas at 25 degrees C were measured using the newly prepared activated carbons. The adsorption capacities of methane gas on the activated carbons at 25 degrees C were one and a half times as much as those of commercially available activated carbon. The adsorption results revealed that the adsorption capacities of methane gas on activated carbons were particularly influenced by their micropore volume.