| Summary: | 碩士 === 中原大學 === 環境工程學系 === 105 === Photochemical smog were formed when emissions containing nitrogen oxide, such as car exhaust, interact with volatile organic compounds in the presence of sunlight. The ground-level ozone were formed by the combination of oxygen in the compounds and the heat from the sunlight. Also, acid rain was formed by the combination of nitrogen dioxide and sulfite with moisture in the atmosphere, and were lead nitric and sulfuric acids. Activated carbon is a form of carbon processed to have small, low-volume pores that increase the surface area available for adsorption or chemical reactions. Active carbon adsorption has numerous applications in removing pollutants from air or water streams both in the field and in industrial processes such as: Drinking water filtration and Air purification.
In this study, the activated carbon with a smooth and smooth carbon ball structure can be obtained by using glucose as the raw material for the preparation of activated carbon. As a result of SEM and BET analysis shows the process of making activated carbon K2CO3 activation, might lead the activated carbon got a better porosity(pore size about 2.03 nm) and specific surface area (1,181.5 m2/g). According to the results of particle size analysis of activated carbon, about 35% of activated carbon is between 0.149 and 0.25 nm, and about 50% of activated carbon is between 0.106 and 0.149 nm, and about 15% of activated carbon less than 0.106 nm.
The NOx adsorption capacity of activated carbon was measured by three flow rates of 3,000 ml / min, 2,000 ml / min, and 1,000 ml / min at a fixed NOX concentration of 1,000 ppb. In the experiment of adsorption concentration, the lowest flow rate of 1,000 ml / min of the best performance, and the adsorption concentration of 490 ppb, after 72 hours its concentration was 752 ppb, may still not reach the saturation concentration. In addition, the adsorption capacity of as-prepared material was same as the flow of 1,000 ml / min were best performance in 24 hours cumulative adsorption capacity of up to 364 mg / g or more. However, under the experimental conditions NOX concentration of 1,000 ppb and flow rate of 3,000 ml / min. After the regeneration of activated carbon, its effect of adsorption can still maintain about 890ppb after 24, and the cumulative adsorption capacity of 355 mg / g.
In addition, the adsorption capacity of activated carbon and commercially available activated carbon for NOX was compared with that in the same NOX concentration of 1,000 ppb and flow rate of 3,000 ml / min. The results show that the optimum adsorption concentration of commercially activated carbon was 798 ppb, the saturation time was 9 hours, and the cumulative adsorption capacity was 86 mg / g after 24 hours; On the other hand, the optimum adsorption concentration of as-prepared activated carbon was 730 ppb, the saturation time reached was19 hours, and the cumulative adsorption capacity was about 268 mg / g after 24 hours. The overall adsorption capacity of activated carbon in this study was much higher than commercial activated carbon.
From the iodine value analysis results, the study of self-made activated carbon iodine value of about 2,291mg / g. Compared with the purchase standard (600 ~ 1,250mg / g) of the six kinds of powdered activated carbon in the garbage collection (incineration) plant in the south of Taiwan, the iodine value of the self-made activated carbon is obviously superior. The experimental results show that the experimental flow rate was too fast and the residence time was too short to show the best adsorption benefit of as-prepared activated carbon.
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