| Summary: | 碩士 === 國立宜蘭大學 === 環境工程學系碩士班 === 107 === Mercury is the most threatening substance in flue gas emitted by burning coal. Elemental mercury has low water solubility, long residence time in the atmosphere, and long transmission distance is a global environmental issue. At present, the way in which flue gas is captured by coal-fired plants is mainly activated carbon adsorption. In this study, hydrothermal method was used to convert waste tires into sulfur-containing activated carbon, which was then used to adsorb and capture mercury vapor. We fixed the time and temperature of hydrothermal carbonization, changed the proportion of waste tire powder/activator, and added the activator into the process in one step and two steps, comparing the sulfur-containing activated carbon produced by the two processes to adsorb mercury vapor. Ability and mechanism. The prepared sulfur-containing activated carbon was observed by field emission scanning electron microscopy (FE-SEM) to observe the change of the morphology of the material, and the elemental analyzer (EA) was used to know the ratio of different elements of the material and the thermogravimetric analyzer (TGA). The sulfur-containing activated carbon produced by waste tires has the content of impurities, and its specific surface area is measured by isothermal adsorption/desorption of nitrogen to evaluate the adsorption capacity of the material and other characteristic analysis to prove the adsorption capacity of the material. The specific surface area of the activated carbon obtained in the two-step process can reach 409.1 m2/g, and the specific surface area of the activated carbon obtained in the one-step process is 157.6 m2/g. Two processes of sulfur-containing activated carbon were used to adsorb mercury vapor and compared using commercial activated carbon on the market. The results of the elemental mercury vapor adsorption experiments under the experimental conditions show that the optimal conditions are the one-step process of activated carbon, the adsorption capacity is 58.05 μg / g, while the commercial activated carbon BPL and FGD adsorption capacity is 53.03 μg /g and 70.76 μg/g. The cost of the activated carbon obtained in the one-step process of this study is estimated to be 465 NT/kg, which is much cheaper than the commercial activated carbon of about 800-1200 NT/kg. This study successfully converted waste tires into sulfur-containing activated carbon and has excellent mercury adsorption capacity, which can effectively recycle waste tires.
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