Adsorption Of Carbon Dioxide On Porous Materials Loading With Potassium Bicarbonate

The Greenhouse effect is one of the greatest environmental problems facing mankind at present. The main reason for global warming is a large number of greenhouse gas emissions. Of all greenhouse gases, with the highest concentration, CO2 accounts for about 55% contribution. Therefore, controlling CO2 emissions is the key to slowing the greenhouse effect. CO2 emissions in the atmosphere are primarily from fossil fuel combustion, produced by man-made burning fossil fuels accounted for 80% of CO2 emissions,1/3 of which from power plants. Therefore, power plant flue gas CO2 capture is the key to reducing greenhouse gas emissions. Research and development of CO2 capture technology becomes the current environment and related fields of research focus. The study focus on fixed-bed adsorption experiments of KHCO3 loding with activated carbon, zeolite, and alumina, and effects of temperature, atmosphere conditions, gas flow rate and cycle performance on the adsorption process are discussed, which will provide the theoretical principle and experimental data of the promotion of applications for future theoretical, is of great practical value.In the process of Preparation and Characterization of the adsorbents. SEM and BET analysis showed that as the load rate increases, more and more KHCO? were adhered to hole and surface of activated carbon, specific surface area and total pore volume of carbon-based adsorbent decreased, and with 5 and 10 cycles, surface area and total pore volume were without significant changes.The load rate of the molecular sieve or alumina as the carrier adsorbents was less than carbon-based adsorbent, surface area and total pore volume were also lower than the carbon-based adsorbent, and the saturation adsorption volume is also poor. All things considered, the highest load rate of carbon-based adsorbent is selected as the main analysis.As the impact factor with carbon-based adsorbent in the adsorption, with the load rate increases, the time to reach the point of penetration and adsorption equilibrium are longer. With the adsorption temperature of 60℃. after 3 cycles, no significant reduction in adsorption accured in the three kinds of adsorbents, they all can reach in the complete regeneration at 200℃for 1h regeneration. Gas flow rate increased from 150mL/min to 200mL/min, time of break-through is lOminiutes ahead, water vapor concentration increased from 10% to 16%,7minutes prolonged, and water vapor concentration is one of the most important factors on the carbonation process.We add water vapor pretreatment to activate adsorbent. In this experimental system, the optimum conditions are as follows:the regeneration temperature 200℃, gas flow rate 150mL/min, adsorption temperature 60℃,8% of CO2,16% of H2O, adding water pretreatment content 3.5mL, the high load rate of carbon-based adsorbent can achieve efficient adsoption and regeneration, and after 10 cycles of this system, the adsorbent can maintain high activity.In the amount of carbon-based adsorbent adsorption studies, the higher the load rate, the greater the amount of saturated adsorption, activation can enhanced saturated adsorption capacity. Of which the high load rate of carbon-based adsorbent range from 38.28 to 47.19 mg/g and the average adsorption capacity of 43.20mg/g, after 10 adsorption regeneration cycles, with no conspicuous saturation adsorption capacity decreased.