Recently, the Innovation Team of Energy-Water-Air (ITEWA) from Shanghai Jiao Tong University has carried out researches on direct air capture of CO2. A new family of amine functionalized DAC adsorbent was reported by impregnating branched polyethyleneimine onto mixed metal oxide nanosheets, which exhibits excellent CO2 adsorption capacity (2.27 mmol/g) and kinetics (1.1 mmol/g∙h) under 400 ppm CO2 as well as good thermal stability and hydrothermal stability with almost no performance degradation after 20 adsorption cycles (DOI: 10.1039/D0TA05079B). On this basis, a three-step steam-assisted temperature vacuum swing adsorption (S-TVSA) cycle was designed for DAC (DOI: 10.1016/j.rser.2020.110651). Simulation results show that the S-TVSA cycle could capture CO2 at a rate of 4.45 mol/kg·day. By using novel adsorbents with better adsorption capacities and kinetics, the capture rate can be further increased by 280% and the energy consumption reduced to 32.8%.
