Experimental and Computational Investigation of CO2 Capture on Mix-ligand Metal-organic Framework UiO-66

Abstract

A mixed-ligand Zr-MOF material has been synthesized as CO2 adsorbents with varous carboxylic acid ligands has for CO2 capture at room temperature. With the purpose of better understanding the thermodynamics and mechanisms of CO2 adsorption, molecular dynamics (MD) simulations have been used to study adsorption kinetics of Zr-MOF adsorbents as well as sorbent structures optimization, and the CO2 adsorption capacity was also simulated by the Monte Carlo (MC) method. Results showed that the CO2 uptake of UiO-66-NH2 under room temperature and pressure reached 134mg/g-sorb. The adsorption capacity of CO2 under low pressure (less than 120kPa) was mainly determined by the pore properties and surface modifications, while the steric hindrance had less influence. The ideal separation factor of UiO-66-NH2-50 were calculated to be 39.7, which showed the excellent CO2/N2 separation performance at 298K.