| Since the industrial revolution, the large-scale use of fossil energy has brought great progress of human civilization. At the same time, a series of environmental and ecological problems are caused by the greenhouse gas emission mainly from fossil fuel burning. Carbon dioxide (CO2), the main greenhouse gas, its emission reduction, capture and use are the urgent global issue. In recent years, due to the low energy consumption, low energy consumption, weak equipment corrosion and high selectivity, the solid amine adsorption method has attracted wide attention in the field of CO2 capture.In this thesis, using carbon materials as support, the monolithic conductive solid amine adsorbent was prepared. The CO2 adsorption/desorption properties of the self designed flow-through absorption component based on the monolithic conductive solid amine adsorbents were studied. The contents of current thesis include:chemical modification of the coal based tubular microporous membrane surface in the different oxidation systems (including:nitric acid, sulfuric acid and nitric acid mixed acid, potassium bisulfate and hydrogen peroxide), and the resulted monolithic conductive solid amine adsorbents were characterized by scanning electron microscopy, infrared and thermal weight technologies. The effects of different oxidation system on the surface oxygen groups were investigated. The monolithic conductive solid amine adsorbents with different organic amines as precursors were prepared by impregnation method. The electrothermal properties of the monolithic conductive solid amine adsorbents were studied under constant current conditions; and the CO2 absorption/desorption properties were then studied by dynamic adsorption method.The main points of this thesis are summarized as follows:(1) After chemical modification, the content of oxygen containing groups of the support (carbon materials) increased greatly, but the compressive strength decreased. Among them, the support after mixed acid oxidation has the highest carboxyl content, up to 0.2749 mol/g. Rich surface containing oxygen groups is found to be favorable to the adsorption of organic amine, the loading amount amine on the solid amine adsorbents can reach up to 27.42%. After the impregnation of the organic amine, the mechanical strength of the monolithic conductive solid amine adsorbent was improved, and the compressive strength can reach up to 68.0 N/cm. Under the condition of constant voltage, the temperature of the monolithic conductive solid amine adsorbent component was raised rapidly, and the cooling rate was also fast after cut-off the power supply.(2) The CO2 adsorption performances of the monolithic conductive solid amine adsorbents are remarkable with short penetration time and large adsorption capacity. Adsorption experiments of different mixed gas flow rate and CO2 concentration showed that with the mixed gas flow rate increases, the amount of adsorption of CO2 decreases; with the increase of CO2 concentration, the amount of CO2 adsorption increases. The results indicate that the prepared adsorbent is suitable for the occasions of high concentration and low flow adsorption. With mixed amine loading, CO2 adsorption capacity can reached up to 143.25 mg CO2/g adsorbent. The monolithic conductive solid amine adsorbents has fast desorption dynamics. Electrothermal desorption experiments showed that the complete desorption time of CO2 less than 10 min. The monolithic conductive solid amine adsorbents has good cycle stability, study the cycle experiments of CO2 adsorption/desorption show the adsorption capacity retention rate of the solid amine adsorbents after five times can reach up to 83%. |
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