Effect of NiO Supported on Activated Carbon for Adsorption and Desorption of MEK Vapor

　　　　　本研究主要探討活性碳浸添NiO對甲基乙基酮蒸氣吸脫附的影響。研究上利用孔隙分析儀、ICP等分析活性碳浸添NiO對其物化特性的改變，並以吸附系統及TGA分析儀探討其對甲基乙基酮蒸氣吸脫附的影響。研究結果顯示；隨著浸添NiO量的增加活性碳，活性碳比表面積與體積有逐漸變小，而孔隙分佈平均直徑有變大現象。對於甲基乙基酮蒸氣吸附特性顯示；在少量添加NiO的活性碳有較佳的吸附特性（吸附容量、吸附速率常數、空床長度等）。至於脫附特性則顯示；活性碳在添加NiO後約可降低熱脫附溫度30-40℃，而分析此原因發現NiO的添加將增加其熱脫附外觀活化能與速率常數。
　　　　　In this investigation. NiO supported on activated carbons were prepared. The properties of specific surface area, pore volume, and chemical metal content of the adsorbents were char-acterized by micropore analysis, ICP, and X-Ray diffraction (XRD). The adsorption apparatus and TGA instrument were used to measure the kinetic data of adsorption and thermal desorption for MEK vapor. All experimental results were used to evaluate the effect of NiO supported on activated carbon for adsorption and thermal desorption of MEK vapor. The results showed that when AC was impregnated with a highly concentrated solution of Ni nitrate, the pores of the activated carbon may be blocked and the favorable geometrical arrangement of adsorbed molecules over the surface may be hindered. Comparisons of adsorption capacity, the length of unused bed (LUB), adsorption zone (H ), and adsorption rate constants of activated carbon and activated carbon with NiO additive showed that AC-0.1 M NiO had the best characteristics for the adsorption of MEK vapor. From thermal desorption tests, the completed temperature (Te) of the activated carbon with NiO additive significantly decreased by about 30-40℃, in the thermal desorption process. The apparent activation energies of adsorbents for MEK in the thermal desorption process were 29.0-36.6kJ/mole. NiO addition to activated carbon increased both the apparent activation energy and the rate constant.