交联羧甲基壳聚糖的合成及其对Pb2+、Cd2+和Co2+的吸附行为

在超声波辐射作用下，以非质子溶剂二甲亚砜为溶剂，制备了新型吸附剂交联羧甲基壳聚糖。利用X-射线光电子能谱、傅里叶红外光谱等分析手段对样品进行了测试和表征。以Pb²⁺、Cd²⁺和Co²⁺为吸附对象，考察了溶液初始浓度、吸附时间、酸度等因素对吸附过程的影响。等温线实验表明Langmuir吸附模型适合模拟金属离子在交联羧甲基壳聚糖表面的吸附过程，说明金属离子在交联羧甲基壳聚糖表面的吸附为单分子层吸附，交联羧甲基壳聚糖对Pb²⁺、Cd²⁺和Co²⁺的最大吸附容量分别为282.49mg/g、328.95mg/g和134.41mg/g。动力学实验表明，准二级方程适合描述此吸附过程。

Synthesis of cross-linked carboxymethyl chitosan and its adsorption capacity for Pb2+, Cd2+ and Co2+

Under ultrasonic irradiation,with aprotic solvent dimethyl sulfoxide as solvent,a novel adsorbent cross-linked carboxymethyl chitosan was prepared. X-ray photoelectron spectroscopy and Fourier transform infrared spectrometry were employed for testing and characterization of the samples. With Pb²⁺,Cd²⁺ and Co²⁺ as the adsorbed objects,the influence of the initial concentration,adsorption time,pH and other factors on the adsorption process were investigated. Isotherm tests showed that the Langmuir adsorption model is suitable for simulation of the adsorption process of the metal ions on the surface of the cross-linked carboxymethyl chitosan,indicating that adsorption of the metal ions on the surface of the cross-linked carboxymethyl chitosan is monolayer adsorption and the maximum adsorption capacity of cross-linked carboxymethyl chitosan for Pb²⁺,Cd²⁺ and Co²⁺ was 282.49 mg/g,328.95 mg/g and 134.41 mg/g,respectively. Kinetic experiments showed that the pseudo-second-order equation was suitable to describe the adsorption process.