Abstract: The N2/CH4 dynamic adsorption behaviors in eleven commercial adsorbents were investigated. The N2/CH4 separation properties of the adsorbents were discussed by adsorption equilibrium，adsorption thermodynamics and adsorption kinetics，from which the correlation coefficients of adsorption equilibrium，adsorption thermodynamics and adsorption kinetics for N2 and CH4 on the adsorbents were obtained. With Langmuir adsorption model and Freundlich adsorption model，the liner fittings were performed for the N2 and CH4 adsorption equilibrium data. It was found that for the microporous activated carbons，the data could be well fitted by both models，while the linear fitting was an unsatisfactory for non-carbonaceous adsorbents and non-microporous carbon adsorbents. With Gibbs adsorption equation，the N2 and CH4 Gibbs free energies adsorbed in the adsorbents were all below zero， suggesting that the N2 and CH4 adsorption processes in the adsorbents were spontaneous. For carbon adsorbents，the difference of CH4 and N2 Gibbs free energies was lower than zero，indicating that carbon adsorbents had stronger adsorption on CH4 adsorbed than N2. At the same time，there was a certain relation of the CH4/N2 separation factor （α）of the adsorbents and the difference of CH4 and N2 Gibbs free energies. For adsorption kinetics，CH4 adsorption kinetic process in AC1 was studied at different adsorption pressures. The data could be well described with the pseudo-second order kinetic model，indicating that the surface adsorption was the rate-determining process during the process of CH4 adsorption in AC1.

Key words: adsorbent, nitrogen, methane, separation, isotherm, thermodynamics, kinetics

摘要： 对N2/CH4在11种不同商业吸附剂上的动态吸附行为进行了研究。通过吸附平衡、吸附热力学和吸附动力学分析了它们对N2/CH4的吸附分离特性，得到了N2和CH4在各吸附剂上的吸附平衡、吸附热力学和吸附动力学基础数据。通过Langmuir吸附模型和Freundlich吸附模型对N2和CH4在吸附剂上的吸附平衡数据进行线性拟合时发现，对于微孔性活性炭两种模型都能达到较好的拟合结果，而对非炭质吸附剂或非微孔性炭质吸附剂拟合结果并不理想；采用Gibbs方程计算得到的吸附剂对吸附N2和CH4的ΔG都小于0，说明所选吸附剂对N2和CH4的吸附都是自发的过程，对于炭质吸附剂吸附CH4的ΔG小于吸附N2的ΔG，说明炭质吸附剂对CH4的吸附能力较N2要大，且CH4/N2的分离系数与吸附剂对吸附CH4和N2的ΔG差值之间也存在相关性；CH4/N2在AC1上的吸附行为符合准二级动力学模型，说明CH4在吸附剂AC1上的吸附行为由表面吸附过程控制。

关键词: 吸附剂, 氮气, 甲烷, 分离, 等温线, 热力学, 动力学