(A) study on the effect of polyethylenimine structure on carbon dioxide isotherms in direct air capture situations

Abstract

The increase in atmospheric carbon dioxide has emerged as a global problem. Energy-efficient capture of carbon dioxide is a way to solve this problem, and among them, direct air capture (DAC) is a way to fundamentally reduce the level of carbon dioxide in the atmosphere. Direct air capture of carbon dioxide allows for the capture of carbon dioxide from mobile sources such as automobiles, trucks, and aircraft, as well as from large industrial facilities, which are fixed sources of emissions. The challenge is to selectively capture about 400 carbon dioxide molecules from 1 million gas molecules present in the atmosphere. In this study, we confirm how SBA-15 silica-polyethyleneimine (PEI) composites affect carbon dioxide adsorption performance depending on the structure of polyethyleneimine, and analyze the energy-efficient adsorption in direct air capture situations. It shows that the manufacture of an adsorbent that physically impregnates polyethyleneimine into SBA-15 silica is an easy method of manufacturing a carbon dioxide adsorbent under direct air collection conditions. Analysis of the SBA-15 silica-polyethyleneimine (PEI) composites prepared by the same method and the carbon dioxide isotherm suggests that the filling ratio of polyethyleneimine in the pore structure of silica is a method for efficient carbon dioxide adsorption.