中文摘要：

采用30℃和90℃的NaCl溶液改性浙江缙云产天然沸石,通过静态吸附实验考察天然沸石及改性沸石对溶液中氨氮的吸附能力及机制,结果表明,NaCl改性可以提高沸石对氨氮的吸附能力。天然沸石及NaCl改性沸石对氨氮的吸附动力学过程符合＂初期快速吸附,后期缓慢稳定＂的特点。假二级动力学模型适合描述天然沸石及NaCl改性沸石对氨氮的吸附过程,颗粒内扩散模型仅适合于描述吸附反应初期天然沸石及NaCl改性沸石对氨氮的吸附过程。天然沸石和NaCl改性沸石对溶液中氨氮的吸附过程满足Langmuir和Freundlich等温吸附模型。90℃NaCl改性沸石、30℃NaCl改性沸石及天然沸石的氨氮饱和吸附量分别为19.5 mg/g、17.8 mg/g和17.2 mg/g。离子交换作用决定了溶液中氨氮向天然沸石及NaCl改性沸石的全部转移量。

英文摘要：

In this study,natural zeolite pretreated by sodium chloride solution under thermal treatment was used to remove ammonium from aqueous solution.Adsorption kinetics,adsorption equilibrium isotherms and adsorption mechanism were investigated by conducting a series of batch experiments.The results indicated that NaCl modified zeolite exhibited higher ammonium adsorption capacity than natural zeolite.The kinetic studies showed that the adsorption of ammonium onto natural zeolite and NaCl modified zeolite could be described by the pseudo-second-order kinetic model and followed the intra-particle diffusion model only during the initial stage of the adsorption process.The results from adsorption equilibrium studies indicated that the Freundlich and Langmuir isotherm models were well fitted to experimental data.The maximum adsorption capacity of zeolite treated by 90 ℃ NaCl solution,zeolite treated by 30 ℃ NaCl solution,and natural zeolite were 19.5 mg/g,17.8 mg/g and 17.2 mg/g,respectively.The results also showed that the adsorption of ammonium from aqueous solution by the natural zeolite and the zeolite treated by NaCl solution is predominated by ion exchange,whereas physical adsorption has little influence.