Tăng cường khả năng bắt giữ khí SO2 của M2(BDC)2TED (M = Mg, V, Co, or Ni) bằng nghiên cứu tính toán

Abstract

Along with finding and developing sustainable clean energy sources, environmental protection is highly urgent because the air is increasingly polluted by more and more toxic gases. In particular, the presence of toxic gas SO₂ seriously affects human health. Therefore, removing toxic SO₂ gas to clean the living environment is extremely urgent. Many technologies have been suggested to solve this, but they have not been effective yet. In recent years, the emergence of porous materials with ultra-large specific surface areas and ultra-high porosity has attracted the attention of scientists in SO₂ capture. Among porous materials, metal-organic frameworks are intensely interested in adsorption, separation, and other potential applications. Herein, we select the porous materials M₂(BDC)₂TED (M = Mg, V, Co, Ni) to study the SO₂ capture using simulation approaches. The research was performed at room temperature 298 K and pressure under 2.5 bar. Our results show that the order of metals gradually increasing the SO₂ adsorption uptake in M₂(BDC)₂(TED) is Co < Ni < V < Mg. Specifically, at 298 K and 2.5 bar, the amount of SO₂ adsorption is about 16 mmol/g for Mg-MOF, and about 13 – 14 mol/g for the M-MOF (M = V, Ni, Co). The study also elucidated the influencing factors that enhance SO₂ adsorption in M₂(BDC)₂TED, including adsorption isosteric heat, specific surface area, and pore volume. Noticeably, the specific surface areas and pore volumes of M-MOFs almost linearly enhance the SO₂ capture capability at room temperature and low pressure. Furthermore, we also elucidate the orbital interaction nature between SO₂ and M₂(BDC)₂(TED) MOFs in detail. Therein, the DOS peaks of the SO₂ adsorbate mainly interact with the adsorbents' C and O p orbitals below the Fermi level.