Molecular Simulation Study Of Flue Gas Separation In Metal-Organic And Covalent Organic Frameworks

Metal-Organic Frameworks (MOFs) and Covalent Organic Frameworks (COFs) are new nanoporous materials with similar structure to zeolites. MOFs and COFs have complex structures, excellent performances and great research value. Computational chemistry methods have been widely used in the study of MOFs and COFs. Through this method, researchers can not only study properties of materials from the microscopic level, but also can predict the structure target materials, reducing the cost of experimental research, which can also speed up the research process.In this paper, molecular simulation was used to investigate the performance of carbon dioxide separation from flue gas in MOFs and COFs, as well as the effects of impurities on the performance of the materials. Because these two types of materials have different structures, they were discussed respectively. The main contents of this paper are as follows:1. Molecular simulations were performed to investigate the effects of impurities (H2O, O2 and SO2) on flue gas separation performance of five MOFs (ZIF-8, NOTT-300, UiO-66(Zr), UiO-66-NH2 and UiO-66-2COOH) and seven COFs (TpBD, TpPa-1, TpPa-2, COF-42-bnn, COF-42-gra, COF-43-bnn and COF-43-gra) in the real flue gas. The simulation results show that H2O has the greatest effect on MOFs and COFs. O2 and SO2 have a negligible effect on the MOFs, while SO2 has a slight influence on the separation performance of the COFs.2. Molecular simulations were also used to respectively study the performance of flue gas separated by the above MOFs and COFs under the industrial conditions. The current study demonstrates that UiO-66-2COOH and TpPa-1 have the highest CO2/N2 selectivity in the dry flue gas, while UiO-66-NH2 and COF-42-gra have the highest CO2/N2 selectivity in the moist flue gas. Comparing the two types of materials of in the same environment, MOFs have higher CO2/N2 selectivity.