Investigation on Performances of the Novel Ammonia-based Hydrogen Storage Material CaCl_2

Ammonia absorption/desorption properties of CaCl_2 and effects of the operation temper- ature,starting pressure and ball milling treatment were investigated.The post-2h milled sample can be fully ammoniated to form CaCl_2(NH_3)_8 within 15min under 20℃and 0.55MPa,and the ammo- nia storage capacity is 55.1wt%,equivalent to be 9.72 wt% of hydrogen.NH3 can be desorbed from CaCl_2(NH_3)_8 in the temperature range from 20℃to 300℃with three stages controlled by temperature and pressure.Six NH_3 molecules can be desorbed at ambient temperature and pressure.Combined with NH_3 decomposition catalyst,CaCl_2 may be one of promising ammonia-based hydrogen storage materials with high capacity.Further investigations indicate that higher operation temperature and starting pressure can improve the ammonia absorption kinetics of CaCl_2,and prolonging ball-milling time can decrease the operation temperature for ammonia desorption of CaCl_2(NH_3)_8 and improve its ammonia desorption kinetics.