CH_4和N_2在炭分子筛及13X沸石上的吸附分离

Adsorptive Separation of CH_4 and N_2 on Carbon Molecular Sieve and 13X Zeolite

采用静态体积法测试了298.15K,313.15K和328.15K时,CH_4和N_2在太西煤基炭分子筛(T-CMS)及13X沸石上的吸附量,并使用Langmuir模型对吸附量数据进行了线性拟合,分析了拟合参数饱和吸附量qm和吸附平衡常数b值的变化.结果表明:随着温度的升高,CH_4在T-CMS上的饱和吸附量qm稍有减少,但变化不大,N_2在T-CMS上的饱和吸附量qm呈增大趋势;CH_4和N_2在13X沸石上的饱和吸附量qm均呈减小趋势,CH_4和N_2在T-CMS及13X沸石上的吸附平衡常数b值均随温度的升高而减小;CH_4和N_2在T-CMS上的分离系数均大于其在13X沸石上的分离系数,分离系数均随温度升高而减小.吸附热力学分析表明,CH_4和N_2在T-CMS上的等量吸附热平均值分别为27.30kJ/mol和22.43kJ/mol,而在13X沸石上的等量吸附热平均值分别为12.96kJ/mol和10.41kJ/mol,两种吸附剂对CH_4的吸附作用均强于其对N_2的吸附作用,且均属于物理吸附.

Adsorption quantity of CH4 and N2 on T-CMS and 13 Xzeolite at 298.15 K,313.15 K and 328.15 K were measured respectively,Langmuir model was used to fit the experimental data,and the change of fitting parameters,saturated adsorption capacity qmand adsorption equilibrium constant b,were analyzed.The results show that the qm of CH4 on T-CMS slightly decreases as the temperatures rise,but the variation is small;the qm of N2 on T-CMS increases;and the qmof CH4 and N2on 13 Xzeolite decreases.However,the adsorption equilibrium constant bincreases with the rising of temperature.Separation coefficients of CH4 and N2on T-CMS are larger than that on 13 Xzeolite,and both decrease with the increase of temperature.The analysis of adsorption thermodynamics shows that the average adsorption isosteric heat of CH4 and N2 on T-CMS are 27.30kJ/mol and 22.43kJ/mol respectively,but that on 13 Xzeolite are 12.96kJ/mol and 10.41kJ/mol respectively.The studied adsorbents have stronger adsorption effect on CH4 than that on N2,which both belong to physical adsorption.