摘要
考察了市售ZSM-5沸石分子筛的碱改性及其吸附去除水中重金属离子Cu2+的效果。研究结果表明,碱改性可有效提高材料吸附容量,经0.40 mol/L氢氧化钠碱改性效果最好。以碱改性分子筛为研究对象,研究其吸附动力学及吸附等温过程,结果表明:吸附过程符合假二阶动力学模型;吸附等温线符合Langmuir等温模型,极限吸附容量达40.49 mg/g。考察投加量、干扰离子等影响因素对碱改性分子筛吸附去除Cu2+离子的影响,对于初始浓度50 mg/L的Cu2+离子,改性材料投加量为0.4~2.4 g/L时,吸附去除率随投加量的增大而增大;当投加量大于1.6 g/L时,对铜离子去除率均在97%以上。当干扰离子Na+、K+、Mg2+、Pb2+与Cu2+离子共存时,Pb2+的干扰影响最大,去除率由不加干扰离子时的98.3%下降至56.5%。此外,采用BET和XRD手段对改性前后的材料进行了表征,并对改性机理进行了探讨。
Alkali treatment of zeolite molecular sieve and its adsorptive performance toward Cu2 +ion from aqueous solution was investigated. The results showed that alkali solution treatment could enhance adsorbing Cu2 +from aqueous solution effectively.Zeolite treated with 0. 40 mol /L NaOH solution exhibits the highest adsorption capacity. Adsorption kinetics and isotherm of Cu2 +uptake using alkali modified zeolite molecular could be satisfactorily described with pseudo second-order kinetics model and Langmuir model. The maximum adsorption capacity calculated by Langmuir model was 40. 49 mg /g. The effect of adsorbent dosage and co-existing cations was explored. When the adsorbent dosage increased from 0. 4 to 2. 4 g /L with 50 mg /L Cu2 +initial concentration,the removal rate increased correspondingly. When adsorbent dosage was more than 1. 6 g /L,the removal rate was higher than 97%. When the common cation Na+,K+,Mg2 +and Pb2 +co-existed with Cu2 +,Pb2 +affect the adsorption significantly,the removal rate reduced from 98. 3% to 56. 5%. Besides,BET and XRD analysis were employed to characterize the materials in order to speculate the madified mechanism.
出处
《环境工程》
CAS
CSCD
北大核心
2014年第10期26-30,共5页
Environmental Engineering
基金
国家自然科学基金NSFC(No.51208179)
关键词
ZSM-5分子筛
碱改性
吸附
铜离子
ZSM-5 molecular sieve
alkali modification
adsorption
Cu2 +
