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选择3种商品活性炭(煤质炭MAC、杏壳炭XAC、椰壳炭YAC),从其对水中微量药物酰胺咪嗪(carbamaz-epine,CBZ)的吸附平衡、吸附等温式、吸附动力学和热力学等方面详细考察了不同种类活性炭对CBZ的吸附去除规律。实验结果表明,3种活性炭与CBZ接触反应10 h后均达到吸附平衡,对CBZ的平衡吸附量在8.3 mg/g左右;比较了Lang-muir和Freundlich两种吸附等温式,发现Langmuir方程更适合描述3种活性炭对CBZ的吸附过程;计算表明3种活性炭的吸附过程均符合拟二级动力学方程,Weber-Morris方程的模拟结果则说明膜扩散和内扩散共同限制了3种活性炭对CBZ的吸附速率;3种活性炭的Ea值分别为29.87 kJ/mol(MAC)、36.02 kJ/mol(XAC)和38.86 kJ/mol(YAC),表明3种活性炭吸附CBZ时同时发生了物理吸附和化学吸附作用,且以化学吸附为主;20～40℃时3种活性炭的△G均为负值,说明3种活性炭对CBZ的吸附反应可以自发进行;MAC、XAC、YAC的△H值分别为-3.10、-3.05和-3.02 kJ/mol,负值表明吸附过程放热,上述△H值较小则说明温度对CBZ的吸附影响不大;3种活性炭吸附CBZ过程的△S值为0.94 J/(mol.K)(MAC)、2.24 J/(mol.K)(XAC)和2.97 J/(mol.K)(YAC),说明吸附过程熵值增加,在外界条件不改变的情况下该吸附过程不可逆,同时可以看出在3种活性炭中,CBZ分子更倾向于吸附在YAC上。
Three kinds of commercial activated carbons (coal carbon MAC, apricot shell charcoal XAC and coconut shell charcoal YAC) were selected. Their adsorption equilibrium, adsorption isotherm, adsorption kinetics, and kinetics of carbamaz-epine (CBZ) Thermodynamics and other aspects of a detailed examination of different types of activated carbon adsorption of CBZ removal law. The experimental results show that the equilibrium adsorption capacity of CBZ is about 8.3 mg / g when the three kinds of activated carbon are contacted with CBZ for 10 h, respectively. The adsorption isotherms of Langmuir and Freundlich are compared, and the Langmuir equation is more suitable The adsorption process of CBZ on the three kinds of activated carbons is described. The results show that the adsorption processes of the three activated carbons are in line with the pseudo-second-order kinetic equation. The simulation results of Weber-Morris equation show that the membrane diffusion and internal diffusion limit the adsorption of CBZ (EAC) of 29.87 kJ / mol (MAC), 36.02 kJ / mol (XAC) and 38.86 kJ / mol (YAC) for the three activated carbons, respectively, indicating that both activated carbons adsorbed physical adsorption and chemisorption And the main chemical adsorption; △ G of the three kinds of activated carbon at 20 ~ 40 ℃ were negative, indicating that the three kinds of activated carbon on CBZ adsorption reaction can spontaneously; MAC, XAC, YAC △ H values were - 3.10, -3.05 and -3.02 kJ / mol, respectively. The negative values indicate that the adsorption process is exothermic. The smaller value of ΔH indicates that the temperature has little effect on the adsorption of CBZ. The △ S values of CBZ adsorption on the three activated carbons are 0.94 J / (mol. K) (MAC), 2.24 J / (mol.K) (XAC) and 2.97 J / (mol.K) (YAC) Process entropy increases, the irreversible adsorption process in a case where the ambient conditions do not change, and can be seen in three kinds of activated carbon, molecular CBZ tend adsorbed on the YAC.