CO2 adsorption and CO2/CH4 separation using fibrous amine-containing adsorbents: isothermal, kinetic, and thermodynamic behaviours

Abstract

A series of brous aminated adsorbents for CO 2 adsorption were prepared by covalent incorporation of poly (glycidyl methacrylate) (PGMA) by graft copolymerization of GMA onto electron beam (EB) irradiated polyethylene/polypropylene (PE/PP) brous sheets and subsequent amination with ethylenediamine (EDA), diethylenetriamine (DETA) or tetraethylenepentamine (TEPA). The physicochemical properties of the adsorbents were evaluated using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric (TGA) and Brunauer-Emmett-Teller (BET) analysis. Of all adsorbents, TEPA-containing bres showed the highest CO 2 adsorption capacity and thus was further investigated for CO 2 capture from CO 2 /CH 4 mixtures of different gas ratios under various pressures and temperatures. The selectivity of CO 2 over CH 4 and equilibrium isotherms, kinetics, and thermodynamics of the adsorption on the brous aminated adsorbent were all investigated. The Sips model was found to best t the isotherm of CO 2 adsorption suggesting the presence of a combination of monolayer and multilayer adsorptions. The adsorption kinetic data was found to best t Elovich model re ecting chemisorption. The ΔG°, ΔS°, and ΔH° showed positive values suggesting that the adsorption of CO 2 on the present brous adsorbent was nonspontaneous with an increase in randomness implying that the process was endothermic. Overall, it can be suggested that PE/PP-g-PGMA/TEPA adsorbent has a strong potential for separation of CO 2 from NG.

Preparation of an Ultrafine Solid Amine Fiber by Electrospinning and Its CO2 Adsorption Behavior

“…Different from the conventional porous solid amine adsorbents, fibrous adsorbents have the advantage of a larger outer surface area, shorter transmission distance, and better flexibility, which makes fibers have a good application prospect in CO 2 adsorption. − Nevertheless, the adsorption capacity of fibrous solid amine adsorbents is often limited by the number of amino groups on the fiber surface. Whether the fiber is impregnated or grafted with amine, a thick layer of amine polymer would inevitably be formed on the support surface. , An amine layer will not only obstruct the transfer of CO 2 but also hide a large number of adsorption sites, thus affecting the adsorption performance of materials …”