Guo Xuebai, Wu Zhenjun, Lu Zheng, Wang Zelong, Li Shunyi, Madhau Freeman, Guo Ting, Huo Rongqican
Henan Vocational College of Water Conservancy and Environment, Zhengzhou 450008, China.
School of Environmental Engineering, Henan University of Technology, Zhengzhou 450001, China.
Gels. 2024 Jul 28;10(8):503. doi: 10.3390/gels10080503.
The "sol-gel method" was used to prepare spherical chitosan-modified bentonite (SCB) hydrogels in this study. The SCB hydrogels were characterized and used as sorbents to remove tetracycline (TC) from aqueous solutions. The adsorbents were characterized by SEM, XRD, FTIR, TG, and BET techniques. Various characterization results showed that the SCB adsorbent had fewer surface pores and a specific surface area that was 96.6% lower than the powder, but the layered mesoporous structure of bentonite remained unchanged. The adsorption process fit to both the Freundlich model and the pseudo-second-order kinetic model showed that it was a non-monolayer chemical adsorption process affected by intra-particle diffusion. The maximum monolayer adsorption capacity determined by the Langmuir model was 39.49 mg/g. Thermodynamic parameters indicated that adsorption was a spontaneous, endothermic, and entropy-increasing process. In addition, solid-liquid separation was easy with the SCB adsorbent, providing important reference information for the synthesis of SCB as a novel and promising adsorbent for the removal of antibiotics from wastewater at the industrial level.
本研究采用“溶胶-凝胶法”制备了球形壳聚糖改性膨润土（SCB）水凝胶。对SCB水凝胶进行了表征，并将其用作吸附剂从水溶液中去除四环素（TC）。采用扫描电子显微镜（SEM）、X射线衍射仪（XRD）、傅里叶变换红外光谱仪（FTIR）、热重分析仪（TG）和比表面积分析仪（BET）等技术对吸附剂进行了表征。各种表征结果表明，SCB吸附剂的表面孔隙较少，比表面积比粉末状低96.6%，但膨润土的层状介孔结构保持不变。吸附过程符合Freundlich模型和准二级动力学模型，表明这是一个受颗粒内扩散影响的非单层化学吸附过程。由Langmuir模型确定的最大单层吸附容量为39.49 mg/g。热力学参数表明吸附是一个自发、吸热且熵增加的过程。此外，SCB吸附剂易于进行固液分离，为在工业水平上合成SCB作为一种新型且有前景的用于去除废水中抗生素的吸附剂提供了重要的参考信息。
