Shen Xiu-E, Shan Xiao-Quan, Dong De-Ming, Hua Xiu-Yi, Owens Gary
College of Environment and Resources, Jilin University, Changchun 130012, China.
J Colloid Interface Sci. 2009 Feb 1;330(1):1-8. doi: 10.1016/j.jcis.2008.10.023. Epub 2008 Nov 1.
The sorption kinetics and thermodynamics of 1,3-dinitrobenzene (DNB), m-nitrotoluene (mNT), p-nitrophenol (pNP), and nitrobenzene (NB) on as-grown and nitric acid-oxidized multiwalled carbon nanotubes (MWCNTs) were investigated. The sorption kinetics was well described by a pseudo-second-order rate model, while both Langmuir and Freundlich models described the sorption isotherms well and the sorption thermodynamic parameters of equilibrium constant (K(0)), standard free energy (DeltaG), standard enthalpy (DeltaH), and standard entropy changes (DeltaS) were measured. The values of DeltaH and DeltaG suggested that the sorption of nitroaromatics (NACs) onto MWCNTs was exothermic and spontaneous. The structure, number, and position of nitro groups of NACs were the main factors affecting the sorption rate and capacity. Treatment of the MWCNTs with nitric acid increased both the surface area and the pore volume and introduced oxygen-containing functional groups to the MWCNTs, which depressed the sorption of NACs onto MWCNTs.
研究了1,3 - 二硝基苯（DNB）、间硝基甲苯（mNT）、对硝基苯酚（pNP）和硝基苯（NB）在生长态和硝酸氧化的多壁碳纳米管（MWCNTs）上的吸附动力学和热力学。吸附动力学可用准二级速率模型很好地描述，而朗缪尔模型和弗伦德里希模型都能很好地描述吸附等温线，并测量了平衡常数（K(0)）、标准自由能（ΔG）、标准焓（ΔH）和标准熵变（ΔS）等吸附热力学参数。ΔH和ΔG的值表明硝基芳烃（NACs）在MWCNTs上的吸附是放热且自发的。NACs硝基基团的结构、数量和位置是影响吸附速率和吸附容量的主要因素。用硝酸处理MWCNTs增加了其表面积和孔体积，并在MWCNTs上引入了含氧官能团，这降低了NACs在MWCNTs上的吸附。
