Rigid shell and flexible pore for highly efficient and reversible sulfur-carbon co-adsorption by hierarchical porous Mg-gallate@Poly(acrylate)

Abstract

The flue gas from coal combustion emits mass CO₂ and trace SO₂, which are harmful to the environment. To address the aforementioned issues, the development of a high-performance sulfur-carbon co-adsorption material is essential for the simultaneous capture of CO₂ and SO₂. A special hierarchical pore structure of Mg-gallate@Poly(acrylate) is synthesized here by self-nanocrystallization flexible metal–organic frameworks (MOFs) load a rigid and hydrophobic polymer macroporous surface. Adsorption results indicate that this material exhibits more pronounced characteristics, with an equivalent CO₂ adsorption capacity to Mg-gallate powder and a 25 % increase in SO₂ adsorption capacity. Dynamic gas adsorption data show that Mg-gallate@Poly(acrylate) has a fast adsorption rate and easy regeneration. Moreover, the adsorption performance of Mg-gallate@Poly(acrylate) in 2000 ppm SO₂ slightly rises to that in a non-sulfur environment. The adsorption capacity of CO₂ and SO₂ can reach 76.5 and 45 mL/g, respectively. The reason for the sulfur-carbon co-adsorption of this material is further demonstrated by theoretical calculations. Additionally, Mg-gallate@Poly(acrylate) shows excellent hydrothermal stability and cyclic regenerability of SO₂ and CO₂. Thus, these results indicate that Mg-gallate@Poly(acrylate) satisfies the process requirements for sulfur-carbon co-adsorption.