Greatly enhanced reactivity of CaC2 with perchloro- hydrocarbons in a stirring ball mill for the manufacture of alkynyl carbon materials

Calcium carbide (CaC 2 ) is a potential feedstock for various alkynyl chemicals, but its actual activity is very low due to its high lattice energy and insolubility. A stirring ball mill was used here to intensify its reaction with perchloro-hydrocarbons (PCHCs), namely hexachlorobenzene (HCB), hexachloroethane (HCE), tetrachloroethene (TCE) and tetrachloromethane (TCM), forming corresponding alkynyl carbon materials (ACMs), viz. ACM HCB , ACM HCE , ACM TCE and ACM TCM , respectively. The reaction intensification may be ascribed to the activation of CaC 2 and its effective collision with PCHCs by the intensive impingement of the milling balls. The as-prepared ACMs were characterized by XRD, Raman, elemental analysis, XPS, SEM and BET analysis, and their adsorption performance was evaluated. These ACMs are mesoporous materials with over 70% carbon content, varying amount of acetylenic groups, rich micro-pores and high specific areas ranging from 270 to 970 m 2  g −1 . ACM HCB is found to be a promising sorbent with adsorption capacity of 514.7 mg-Hg g −1 for HgCl 2 aqueous solution and 24.4 mg-S g −1 for DBT oil, which is much superior to most of carbonaceous sorbents due to its rich micro-porosity and abundant acetylenic groups.