Abstract: Activated carbon with high specific surface area was prepared from coconut shell charcoal(CsAC), the structural properties of which were measured. The electrochemical performances of electric double-layer capacitor (EDLC) with CsAC as electrode material were investigated, including cyclic voltammetric and constant current charge/discharge properties. Results showed that EDLC had good charge/discharge performance and the specific capacitance of CsAC reached 164 F/g. Adsorption isotherms of NH₃, CO₂, CH₄, N₂, O₂ and H₂ on CsAC were measured at 298K. Considerable difference among the adsorption capacities toward different gases was observed and NH₃ was adsorbed much more than CO₂, CH₄, N₂, O₂ and H₂. According to adsorption amount ratio of two gases, it was concluded that CsAC was a very good adsorbent for the separation of NH₃ from its mixtures such as NH₃/N₂,NH₃/O₂ and NH₃/air. CsAC was also suitable for the separation of NH₃ from its mixture of CH₄,as well as for the separation of CO₂ from its mixtures of O₂ or N₂ or both.

Key words: coconut-shell activated carbon, electrode material, adsorption, high specific surface area