Study on the Adsorption Separation of CHF3/N-2 by an SIFSIX-3-Ni Metal-Organic Framework

CHF3 is a strong greenhouse gas, and its potential greenhouseeffect is 14,800 times that of CO2, so recycling and reusingCHF(3) positively contributes to environmental sustainability.Therefore, a purification and recovery process development based onthe adsorption of CHF3 has become an urgent requirement.In this paper, an ultramicroporous fluorine-containing pillared metal-organicframework (MOF), SIFSIX-3-Ni, was applied to the separation of CHF3/N-2. The adsorption and separation properties ofSIFSIX-3-Ni for CHF3/N-2 were confirmed by single-componentisotherms and binary breakthrough experiments, respectively. The uptakecapacity of CHF3 was 1.03 mmol g(-1) at288 K and 7.0 bar. The selectivity of CHF3/N-2 reaches 23-24 at 288 K and 3.0 bar, exhibiting a high separationselectivity. The pressure swing adsorption (PSA) simulation of treatingthe CHF3/N-2-mixed gas with the actual exhaustgas composition was investigated. The results show that the purityof CHF3 can reach 99%, it can be used as a fire extinguishingagent under the optimized operating conditions, and the recovery rateis over 83%. Experimental studies show that SIFSIX-3-Ni has a goodapplication prospect in the separation of CHF3/N-2.