Department of Chemistry, The Gandhigram Rural Institute - Deemed to be University, Gandhigram, Dindigul, 624 302, Tamil Nadu, India.
Department of Chemistry, The Gandhigram Rural Institute - Deemed to be University, Gandhigram, Dindigul, 624 302, Tamil Nadu, India.
Int J Biol Macromol. 2020 Jul 1;154:188-197. doi: 10.1016/j.ijbiomac.2020.03.074. Epub 2020 Mar 19.
Nitrate and phosphate are primary pollutants of water/wastewaters for eutrophication and methemoglobinemia diseases, harshly threatening the security of aquatic environments and human health as well as all living beings. The present work investigates the adsorption performance and mechanism of lanthanum encapsulated chitosan-kaolin clay (LCK) hybrid composite was prepared and utilized for the remediation of nitrate and phosphate from water. The fabricated LCK hybrid composite was characterized using XRD, SEM, BET, EDAX, TGA-DTA and FTIR analysis. The removal of nitrate and phosphate onto the LCK composite defined by pseudo-second-order kinetic model whereas the isotherms are described by Freundlich adsorption isotherm model and thermodynamic experiments showed spontaneous and exothermic nature of the adsorption process. Results also demonstrated that the LCK hybrid composite exhibited extremely high nitrate and phosphate adsorption capacity and stability which followed the mechanisms by ion exchange, complexation and electrostatic interactions. Adsorption-desorption experiments revealed that the LCK hybrid composite could be potentially reused with maintaining high adsorption efficiency. This study highlights the novel low-cost, eco-friendly and promising adsorbent for efficient denitrification and dephosphorization from water/ wastewater.
硝酸盐和磷酸盐是水体富营养化和高铁血红蛋白病的主要污染物，严重威胁着水环境保护和人类健康以及所有生物的安全。本工作研究了镧封装壳聚糖-高岭土粘土（LCK）杂化复合材料的吸附性能和机理，并用其从水中修复硝酸盐和磷酸盐。通过 XRD、SEM、BET、EDAX、TGA-DTA 和 FTIR 分析对制备的 LCK 杂化复合材料进行了表征。通过拟二级动力学模型定义了 LCK 复合材料对硝酸盐和磷酸盐的去除，而等温线则由 Freundlich 吸附等温线模型描述，热力学实验表明吸附过程是自发和放热的。结果还表明，LCK 杂化复合材料表现出极高的硝酸盐和磷酸盐吸附容量和稳定性，遵循离子交换、络合和静电相互作用的机制。吸附-解吸实验表明，LCK 杂化复合材料可以潜在地重复使用，并保持高的吸附效率。本研究突出了一种新型的低成本、环保且有前途的吸附剂，可有效从水/废水中进行反硝化和除磷。
