以水滑石(LDH)、壳聚糖(CS)、聚吡咯(PPy)为原料,采用原位氧化聚合法制备PPy/CS/LDH复合材料,通过扫描电镜、X射线衍射、傅里叶红外光谱、热重、N2吸附-脱附对其进行表征,研究了pH、Cr(Ⅵ)离子初始浓度、接触时间、温度等对Cr(Ⅵ)离子去除的影响。结果表明,PPy微球覆盖在CS/LDH表面,增大了CS/LDH的比表面积,在298K时,PPy/CS/LDH对Cr(Ⅵ)离子的吸附量最高为349mg/g,优于LDH、CS/LDH吸附剂。PPy/CS/LDH对Cr(Ⅵ)吸附更符合Langmuir吸附等温模型和拟二级动力学模型,说明吸附是发生在吸附剂表面的单分子层吸附。对吸附剂进行吸附-脱附循环实验发现,5次循环后仍保持较高的吸附量。
Polypyrrole/chitosan/hydrotalcite composites (PPy/CS/LDH) were prepared by in-situ oxidative polymerization with hydrotalcite (LDH),chitosan (CS) and polypyrrole (PPy) as raw materials.The composites were characterized by scanning electron microscope,X-ray diffraction,Fourier infrared spectroscopy,thermogravimetry and N2 adsorption and desorption.The effects of pH,initial concentration of Cr(Ⅵ) ions,contact time and temperature on the removal of Cr(Ⅵ) ions were studied.The results showed that the surface of CS/LDH was covered with PPy microspheres,which increased the specific surface area of CS/LDH.At 298K,the maximum adsorption capacity of PPy/CS/LDH for Cr(Ⅵ) ion was 349mg/g,which was better than that of LDH and CS/LDH adsorbents.The adsorption of Cr(Ⅵ) by PPy/CS/LDH was more in line with the pseudo-second-order kinetic model and Langmuir model,indicating that the adsorption was monolayer adsorption on the surface of the adsorbent.The adsorption and desorption cycle experiment of adsorbent was carried out,and the adsorption capacity remained high after five cycles.
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基金资助
黑龙江省省属高等学校基本科研业务费科研项目(145209116)
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