A titanium carbide-derived novel tetrafluoromethane adsorbent with outstanding adsorption performance

Abstract

CF4, which is widely used in the production of semiconductors and aluminum, has a very high global warming potential and extremely long atmospheric lifetime. Adsorption is an alternative technique to the energy-consuming conventional CF4 combustion disposal method, and the development of appropriate adsorbents is important for a competent CF4 adsorption process. Here, microporous carbons are synthesized for new CF4 adsorbents by the selective etching of titanium carbide using chlorine gas at high temperatures (800, 900, and 1000 degrees C). Additionally, post-treatment with H-2 eliminates any unreacted chlorine. Interestingly, the CF4 adsorption capacity has a linear relation with the micropore volume for pores less than 0.9 nm. The titanium carbide-based microporous carbon chlorinated at 800 degrees C and post-treated with H2 has the highest CF4 adsorption capacity of 2.96 mol kg(-1) at 25 degrees C and 1 atm, which is the highest reported value to date. Besides the high CF4 adsorption capacity, the prepared microporous carbon shows a high selectivity for CF4 over N-2 at low CF4 partial pressures and an excellent cyclic stability. (C) 2016 Elsevier B.V. All rights reserved.