摘要
以沸石、陶粒、火山岩为试验材料,分别考察了不同初始氨氮浓度、pH、共存金属阳离子、温度对填料吸附氨氮的影响,并采用了吸附等温线、动力学和热力学对吸附过程进行解析.结果表明,Langmuir方程与Freundlich方程均能较好地描述氨氮在3种填料上的等温吸附行为.3种填料对氨氮的最大吸附量分别为0.9625 mg·g-1(沸石)、0.8643 mg·g-1(火山岩)和0.6928 mg·g-1(陶粒).Freundlich方程中,1/n<0.5,表明3种填料对氨氮的吸附属于优惠吸附.颗粒内扩散不是控制填料吸附NH+4的唯一控速步骤,吸附过程可能受到内扩散和表面吸附的共同影响.pH值介于6—9之间时,对氨氮有较好的去除效果.共存阳离子对氨氮的吸附具有抑制作用,具体表现为Al3+>Mg2+>Na+>Ca2+.等温解吸试验表明,陶粒对氨氮的吸附以物理作用为主,而沸石和火山岩以离子交换为主.
Experiments were conducted on the adsorption properties of ammonia nitrogen by zeolite,ceramsite and lava at different initial concentration,pH,coexisting metal cations and temperature The adsorption isotherms of ammonia nitrogen on the three fillers were fitted with the Langmuir and Freundlich well. The maximal adsorption quantities of ammonia nitrogen on three fillers were0.9625 mg·g^-1（zeolite）,0.8643 mg·g^-1（lava） and 0.6928 mg·g^-1（ceramsite）,respectively. And in the Feundlich equation 1/n 〈0. 5,indicating that the adsorption of ammonia nitrogen by three fillers were preferential. Intra-particle diffusion is not the only step to control the adsorption of NH＋4 by fillers. The process may be the combined action of internal diffusion and surface adsorption. The removed of ammonia nitrogen by fillers was optimal at pH value between 6 and 9. There was an obvious inhibitory effect on adsorption of ammonia nitrogen in the presence of coexisting cations,which followed the order of Al^3＋ 〉Mg^2＋ 〉Na^＋〉 Ca^2＋. The results of desorption experiment showed that physical adsorption maybe the main adsorption mechanism on ceramsite. The adsorption onzeolite and lava was dominated by ion exchange.
作者
刘莹
刘晓晖
张亚茹
王炜亮
LIU Ying;LIU Xiaohui;ZHANG Yaru;WANG Weiliang(College of geography and environment, Shandong Normal University, Ji＇nan, 250358, China;School of Environment, Tsinghua University, Beijing, 100084, China;Institute of Environment and Ecology, Shandong Normal University, Ji＇nan, 250358, China)
出处
《环境化学》
CAS
CSCD
北大核心
2018年第5期1118-1127,共10页
Environmental Chemistry
基金
山东师范大学研究生科研创新基金(SCX201737)
国家自然科学基金(41672340)资助~~
关键词
人工湿地
填料
氨氮
吸附
解吸
constructed wetland
fillers
ammonia nitrogen
adsorption
desorption.
作者简介
通讯联系人:王炜亮,Tel:15990905868,E-mail:sunboyhood@163.com
