Composite method of trapping carbon dioxide in gas mixture

Abstract

A hybrid method for capturing COfrom a gas mixture is provided, comprising a step of contacting the COcontaining gas mixture with a slurry consisting of a liquid medium, imidazole or imidazole derivative(s), and a metal-organic framework material (MOFs). For the slurry system, the mass fraction of the imidazole or imidazole derivative(s) in it ranging from 2 to 50% and the mass fraction of the metal-organic framework material in it ranging from 5 to 25%. In the technical solution provided in the present invention, through combining absorptive separation by the liquid solution in which the imidazole or imidazole derivative(s) is dissolved, adsorption separation by the MOF material suspended in the solution, and selective permeation separation by a liquid medium film forms on the outside surface of the suspended MOFs, an absorption-adsorption hybrid separation effect for COgas mixtures is efficiently achieved. In the COcapture method provided in the present invention, conventional absorption separation and adsorptive separation technologies are effectively combined, furthermore, the addition of imidazole or imidazole derivative(s) substantially increases both the COcapture ability and capture amount of the MOFs/liquid slurry, showing a great potential in industrial applications.