MgO adsorbent has been widely used in the field of CO2 adsorption due to its advantages of low cost, wide source and low regenerative energy consumption, but its adsorption performance is limited by its low surface ratio. In this paper, a phosphine-containing porousorganic polymer POL-PPH3 with high surface area and hierarchical pore structure was used as a carrier, and POL-PPH3-loaded MgO adsorbent (MgO/ POL-PPH3) was prepared by impregnation-calcination and ultrasonic calcinations to obtain the MgO adsorbent (MgO/POL-PPH3) for CO2 capture. Effects of preparation conditions such as preparation method, calcination temperature and calcination timeon the CO2 adsorption performance on MgO/ POL-PPH3 adsorbents were investigated. It is found that the impregnation calcination methodis superior to the ultrasonic calcination method, and the CO2 adsorption capacity on the MgO/ POL-PPH3 samples gradually decreases withthe increase of calcination temperature and calcination time. The optimum CO2 adsorption capacity of 0.55 mmol/ g on MgO/ POL-PPH3-300-1 adsorbent is obtained when the impregnation calcination method is used with a calcination temperature of 300 ℃ and a calcinationtime of 1 h. In the simulated flue gas with a composition of 12% CO2 and the rest of nitrogen, the CO2adsorption capacity of 0.02 mmol/ gon the MgO/ POL-PPH3-300-1 adsorbent is obtained. Under the conditions of adsorption at 200 ℃ for 60 min and desorption at 370 ℃for 15 min, the CO2 adsorption capacity of this adsorbent remains unchanged after five times of stable recycling. The structure-property relationship of CO2 adsorption on MgO/ POL-PPH3 adsorbent was elucidated by combining N2 physical adsorption, thermogravimetric, FT-IR, XRD, SEM-EDX and other characterization methods. Kinetic modelling analysis of the CO2 adsorption behaviours on the three adsorbents obtained at different calcination temperatures by impregnation calcination method is dominated by physical adsorption, whereas thoseof the three adsorbents obtained at different calcination times, including the MgO/ POL-PPH3-300-1 adsorbent, are dominated by chemical adsorption. The high specific surface area and hierarchical pore structure are conducive to the exposure of more active sites and thetransport and diffusion of CO2, which in turn increases the CO2 adsorption capacity of the MgO/ POL-PPH3 adsorbent, and the high dispersion of MgO on the support is also benificial to the enhancement of the contact with CO2 to accelerate the CO2 adsorption rate.

田甜(2000—),女,河北承德人,硕士研究生。E-mail:1742925271@qq.com

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TIAN Tian,ZHANG Xueqi,WANG Yuqing,et al.Preparation and CO2 adsorption performance of a phosphine-containingporous organic polymer supported magnesium oxide[J].Clean Coal Technology,2024,30(4):146-156.