天然斜发沸石粉对溶液中NH_4^+的吸附机理研究  

Adsorption characteristics of ammonium ions by natural clinoptilolite powder

作　　者：张新颖[1] 吴志超[1] 王志伟[1] 周琪[1] 杨殿海[1] 

机构地区：[1]同济大学环境科学与工程学院,上海200092

出　　处：《中国环境科学》2010年第5期609-614,共6页China Environmental Science

基　　金：水体污染控制与治理科技重大专项(2008ZX07316-002)

摘　　要：采用天然斜发沸石粉(平均粒径30μm)进行吸附溶液中NH4+的试验研究,并对系统中金属阳离子的液相和固相含量进行了全程跟踪测定.等温吸附试验、吸附动力学研究结果表明,天然斜发沸石对溶液中NH4+的吸附过程符合Freundlich线性模型(R2=0.996),该吸附过程属于优惠吸附;吸附动力学符合假二级方程(R2>0.99),且随着初始NH4+浓度的增加,吸附反应的优惠程度降低.沸石粉对NH4+的吸附过程中离子交换以Ca2+和Na+为主,Na+首先被交换出来,随着吸附过程进行,Ca2+交换量逐渐增加并超过Na+,两者交换当量分别占39%～60%和35%～57%.由于沸石粉粒径较小,其对NH4+的去除除了依靠离子交换作用外,物理吸附作用的贡献不容忽视.Natural clinoptilolite powder,with an average particle size of 30μm,was selected as experimental material.The adsorption characteristics of the clinoptilolite on NH4＋ in solution were studied,with the monitoring of metal elements concentration in liquid-phase and solid-phase.The isothermal adsorption experiment,adsorption kinetics experiment were conducted.The results showed that the ammonium adsorption by the natural clinoptilolite was fitted well with Freundlich adsorption isotherm （R2=0.996） and the pseudo second-order kinetics （R20.99）.The adsorption process was less favorable with the increase of initial NH4＋ concentration.Na＋,Ca2＋ occupied the major part of the exchange amount in this process.Na＋ was exchanged into liquid-phase first.Then exchange amount of Ca2＋ increased gradually and exceeded Na＋ finally.The exchange amount of Na＋ and Ca2＋ occupied 39%～60% and 35%～57% in the adsorption process,respectively.For the clinoptilolite with fine particle size,besides ion exchange,the contribution of physical adsorption should not be neglected in nitrogen removal process.

关 键 词：天然斜发沸石 氨氮 吸附 离子交换 污水处理 

分 类 号：X703.1[环境科学与工程—环境工程]