A facile approach to the fabrication of MgO@Y composite for CO2 capture

Abstract

Zeolite Y supported MgO (denoted as MgO@Y) composites have been successfully prepared using Mg(NO3)2 as precursor via a facile solid-state heat dispersion approach. The samples are characterized by X-ray diffraction and N2 adsorption/desorption, and investigated for CO2 adsorption performance including adsorption capacity, adsorption selectivity and stability. The results reveal that MgO can be highly dispersed on the surfaces of zeolite Y support after the activation at high temperatures, and the monolayer dispersion capacity of MgO on zeolite Y support is 3 mmol/g zeolite Y. The resulting MgO(3.0)@Y adsorbent with the magnesium loadings of 3 mmol/g zeolite Y displays a high CO2 adsorption capacity of 2.78 mmol/g at 500 kPa, which is about 28% higher than that of zeolite Y support. Moreover, the MgO(3.0)@Y adsorbent displays a high CO2/N2 adsorption selectivity of 32 and a excellent cyclic stability. Its good performance as well as its facile preparation process make it attractive candidate for the adsorption of CO2 in flue gas vents. In addition, the isosteric heat of CO2 adsorption on the MgO(3.0)@Y sample was calculated from the Clausius–Clapeyron equation, and the values the isosteric heats of adsorption lie in the range of 27.8–20.0 kJ/mol.