| Activated carbon was not only an excellent adsorbent, characterized by developed porosity and large surface area, but also it had good chemical stability, high mechanical strength, easy regeneration, et al. It was used extensively in industry, military, chemical engineering, environmental protection, and so on. Recently, with the trend of sustainable development, activated carbon as an environmental-friendly material, attracted great attention for energy storage and advanced water treatment.Currently, researches on preparation of activated carbon were aimed at high adsorption capacity, large surface area, low cost and controllable structure. In this work, two simple and effective methods and relative activation mechanisms were studied to reinforce chemical activation. Besides these, a rotary activation furnace of pilot scale was designed and used to investigate the effects such as temperature, time, ratio and granularity. Activated carbons from pilot preparation were successfully used for adsorbing natural gas and removing N-nitrodimethylamine (NDMA) from water, respectively. Through the characterization of structure and property, the investigation of factors during adsorption, the relationship among porous structure, surface property and the application was founded with the elucidation of adsorption. The main results are as follows.Activated carbon with more developed porous structure was prepared. Due to the combined effects of activation and synergistic activation by steam, activation was reinforced and activation agent got saved in coupling activation. Simultaneously, the activation ability of cation and electron transfer medium of anion by promoting agents like chlorides and bromides of alkali metals and alkali-earth metals, could promote chemical activation else.Through the pilot scale furnace, activated carbons with developed porosity were successfully prepared by KOH and Petroleum coke. When the mass ratio of KOH to fine petroleum coke powder was 4:1, activation temperature was 730℃and activation time was 1.5 hour, activated carbon with surface area 2319m2/g and micropore volume 0.65cm3/g was synthesized. Those activated carbons from pilot preparation had excellent methane adsorption performance under 25℃, 3.5MPa, with more than 15% and the best of 23.86%.In our studies, methane adsorption performance was mainly determined by surface area and micropore volume of activated carbon. Higher surface area and larger micropore volume were better to adsorption. While, more methane could not get released due to extra more micorpores. During adsorption, methane was preferentially adsorbed in micropores with pore filling mechanism. After that, adsorption capacity had slow increase led by compressed methane in mesopores and macropores. Surface modification and metal oxide loading both had less influences to methane storage.The relationship between adsorption potential and average pore size under critical conditions was deduced as equation 5-5. It was found that adsorption potential E0 was decided by micropore size Xav, the smaller of Xav with the higher of E0. The parameter of n in Dubinin-Astakhov had less influence.NDMA in water was removed by activated carbon. The adsorption conditions, porous structures and surface properties were investigated to uncover adsorption mechanism. It was inferred that NDMA had better adsorption on activated carbon than zeolites, with highest capacity of 24mg/g. Porous structure and surface chemistry analysis revealed that NDMA was preferentially adsorbed in micropore around 0.45nm, and adsorption capacity was related with its volume. Thermal treatment could improve hydrophobic surface of activated carbon, and reduce selective adsorption by water molecules. NDMA was more adsorbed with nonpolar methyl ends on hydrophobic site, presenting great improvement of capacity.Finally, TiO2 loaded on activated carbon surface to degrade the adsorbed NDMA was studied. It was concluded that monolayer TiO2 on surface possess great photocatalytic activity. The combination of TiO2/AC showed distinctive synergistic effect to adsorb and decompose NDMA.
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