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sltmac(金币+1): 谢谢交流~~ 2011-05-26 20:44:38
LBC8306(金币+5): 非常感谢 2011-05-26 20:45:00
ringzhu(金币+3, 翻译EPI+1): 楼上家伙不厚道啊 有木有！！ 2011-05-27 20:17:58
Carbon nanotubes with unique constitutive properties such as high thermal stability and chemically inert nature, is commonly considered a good carrier. Composite materials for removing copper ion in water can be prepared from loading alumina onto carbon nanotubes. Here is a discussion on the adsorption properties of this composite absorbent .
The composite absorbent, alumina-supported carbon nanotubes materials (Al2O3/CNTs), was prepared through putting aluminium nitrate into suspension of carbon nanotubes and adding some ammonia. IR and differential thermal analysis(DTA) showed that alumina has been loaded onto carbon nanotubes in the form of γ-Al2O3 and that thermal stability of carbon nanotubes is reduced after loading alumina. The largest adsorption capacity of Al2O3/CNTs can be achieved when 50% alumina is loaded. Adsorption capacity Al2O3/CNTs varied at different solution pH and decreased with the decrease of pH. As the initial concentration of copper ion in solutions increased, Al2O3/CNTs adsorption increased while adsorption rate reduced.
Thermodynamics of copper ions being adsorbed onto Al2O3/CNTs showed that the adsorption was a spontaneous and exothermic process with an increase in entropy. The adsorption process can be described well by Langmuir adsorption model. From Langmuir adsorption isotherm, maximum adsorption capacity Qmax of Al2O3/CNTs to copper ions was determined as 44.445 mg/g. Research on adsorption kinetics elucidate that this adsorption could be described by pseudo-second-order kinetics model well. |
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