Adsorption of Cd(II) in water by mesoporous ceramic functional nanomaterials

Mesoporous Ceramic Functional Nanomaterials (MCFN) is a self-assembled environmental adsorbent with a monolayer molecular which is widely used in the treatment of industrial wastewater and contaminated soil. This work aimed to study the relationship between the adsorption behavior of Cd(II) by MCFN and contact time, initial concentration, MCFN dosage, pH, oscillation rate, and temperature through a batch adsorption method. The adsorption kinetic and isotherm behaviors were well described by the pseudo-second-order and Langmuir models. The batch characterization technique revealed that MCFN had several oxygen-containing functional groups. Using Langmuir model the maximum adsorption capacity of MCFN for Cd(II) was 97.09 (mg/g) at pH 6, 25, dosage of 0.2 g, and contact time of 180. Thermodynamic study indicated that the present adsorption process was feasible, spontaneous and endothermic at the temperature ranging 25 - 55℃. The results of this study provide an important enlightenment for Cd removal or preconcentration of porous ceramic nanomaterials adsorbents for environmental applications.

介孔陶瓷功能纳米材料（Mesoporous Ceramic Functional Nanomaterials，MCFN）是一种具备单分子层特性的自组装型环境吸附剂，被广泛应用于工业废水与污染土壤的治理修复。本研究采用批量吸附实验法，探究了MCFN对Cd(II)的吸附行为与接触时间、初始浓度、MCFN投加量、pH值、振荡速率及温度之间的关联。吸附动力学与吸附等温线行为可分别通过准二级动力学模型与朗缪尔（Langmuir）模型进行良好拟合。批量表征技术分析结果显示，MCFN表面含有多种含氧官能团。基于朗缪尔模型计算可得，在pH为6、温度25℃、投加量0.2g、接触时间180的条件下，MCFN对Cd(II)的最大吸附容量可达97.09 mg/g。热力学研究表明，在25℃至55℃的温度区间内，该吸附过程具备可行性、自发性且为吸热过程。本研究结果可为环境应用领域中多孔陶瓷纳米材料吸附剂的镉去除或预富集工作提供重要参考与启示。