| 摘要: | 本年度研究以化學活化法有效提昇活性碳之孔隙性與表面化學特性.以椰殼為原料,含浸於硫酸亞鐵溶液中,製備觸媒活性碳.探討含浸劑濃度及製備條件不同對觸媒活性碳之表面結構與孔隙特性及其對酚溶液吸附效果之影響.研究結果發現,活性碳的表面積和孔隙體積隨著活化劑濃度增加而減少,而平均孔徑與中孔比例則隨含浸劑濃度增加而增大.於酚溶液的等溫吸附試驗中,由Freundlich吸附方程式的吸附平衡常數(k)與動力級數(n)得知,k與n值與活性碳表面積大小呈正比關係,且於酚的吸附試驗中發現以低含浸濃度製成的活性碳具有較佳的吸附能力.然將觸媒活性碳應用於酚溶液之氧化作用,於反應中加入氧化劑(H<sub>2</sub>O<sub>2</sub>),觸媒活性碳可將H<sub>2</sub>O<sub>2</sub>催化產生．OH自由基而破壞有機污染物,於85 ℃的反應溫度下,高含浸濃度製成之觸媒活性碳具有較高之酚氧化速率,回收反應後之觸媒活性碳,重複進行四次酚的氧化試驗,觸媒活性碳仍具高氧化活性,顯示此型觸媒活性碳除具備傳統活性碳之吸附能力外,亦對有機污染物具有良好之氧化能力.
The chemical activation process was used to enhance the surface chemical and porosity properties of activated carbon. The ferrous sulfate doping in coconut shell was using by immersing procedure. The effect of preparing conditions and concentration of immersing agent on the adsorption efficiency and pore structure of activated carbons were discussed in this study. Based on the results in this investigation, the surface area and pore volume of activated carbon decreased and the average pore-diameter increased with the increase in concentration of immersing agent. The adsorption kinetic was well described by Freundlich equation and the k and n value was proportional to the surface area of activated carbon. It was found that the high sorption capacity was observed in low concentration immersion agent. The porous structure and iron oxide on surface of active carbon were evidenced by SEM-EDS measurement. The catalytic oxidation was processed with hydrogen peroxide in phenol solution by the HO·free radical, which was generated by the active site on the active carbon. The high oxidation efficiency could be obtained at 85 ℃ with a suitable conditions. It was found that the phenol removal did not change even the 4 times reuse in oxidation. The stability test was confirmed the oxidation activity of activated carbon did not decrease. Based on the results of this study, the ability of catalytic oxidation and sorption capacity of activated carbon was superior to the commercial product. |
