摘要
采用化学沉淀法在凹凸棒石的表面负载纳米氧化锌合成了凹凸棒石/氧化锌(ATP/ZnO)纳米复合材料.同时,研究了亚甲基蓝在纳米复合材料上的吸附行为,并从热力学和动力学角度探讨了吸附作用机理.吸附实验表明:纳米复合材料对亚甲基蓝有优异的吸附能力;纳米复合材料对亚甲基蓝的吸附热力学符合Langmuir等温吸附方程,最大吸附量可达110.50mg·g-1,吸附焓变为18.69kJ·mol-1,吸附自由能变为-33.06～-22.74kJ·mol-1,吸附熵变约为146J.mol-1.K-1,是一个自发的吸热过程;纳米复合材料对亚甲基蓝的吸附动力学符合准二级动力学方程,速率常数随着溶液初始浓度的提高而下降.
Nanocomposites of attapulgite supported with nano-ZnO were prepared by chemical coprecipitation.The adsorption capability,adsorption kinetics and thermodynamics of methylene blue on the nanocomposites were studied.The results indicated that the nanocomposites had excellent adsorption capability of methylene blue.The thermodynamics of methylene blue adsorption on the nanocomposites followed the Langmuir adsorption equation.The maximum adsorption amount was 110.50 mg·g^-1,the adsorption enthalpy was 18.69 kJ·mol^-1,the Gibbs free energy was-33.06 - -22.74 kJ·mol^-1,and the entropy was about 146 J·mol^-1·K^-1,so the adsorption process was both endothermic and spontaneous.The kinetics of methylene blue adsorption on nanocomposites fit the pseudo-second order rate law and the rate constant decreased as the initial concentration increased.
出处
《环境科学学报》
CAS
CSCD
北大核心
2010年第6期1211-1219,共9页
Acta Scientiae Circumstantiae
基金
国家高技术研究发展计划(863)项目(No.2007AA06Z118)
江苏省支撑计划(No.BE2008032
BE2008033
BE2009099)
江苏省教育厅项目(No.08KJD430011
09KJA430002)
江苏省自然基金(No.BK2009748)
常州市科技攻关(No.CE2007075
CE2008077)~~
