College of Chemistry, Green Catalysis Center, Zhengzhou University, No. 100 of Kexue Road, Zhengzhou, 450001, People's Republic of China.
Environ Sci Pollut Res Int. 2022 Mar;29(14):20976-20995. doi: 10.1007/s11356-021-16963-z. Epub 2021 Nov 8.
The presence of emerging pollutants such as PO and NO in water bodies has attracted worldwide concern about their severe effects on water bodies and the health of humankind in general. Therefore, to preserve the health of humankind and environmental safety, it is of the essence that industrial effluents are treated before they are discharged into water bodies. Amine functionalized walnut shells (ACWNS) were synthesized, characterized, and then tested as a novel adsorbent for PO and NO removal. The effects of pH, dosage, initial phosphate concentration, interference ions, and temperature on the removal of phosphate and nitrate were investigated. Notably, the adsorption of PO and NO was exothermic and spontaneous, with a maximum uptake capacity of phosphate and nitrate, at 293 K, 82.2 and 35.7 mg g, respectively. The mechanism by which these ions were adsorbed onto ACWNS could be electrostatic interactions and hydrogen bonding. Pseudo-second-order kinetic model fitted the PO and NO adsorption, while Freundlich and Langmuir models best fitted the PO and NO adsorption, respectively. Furthermore, in the binary system, the uptake capacity of phosphate decreased by 14.4% while nitrate witnessed a reduction in its uptake capacity of 10.4%. ACWNS has a higher attraction towards both ions and this could be attributed to the existence of a variety of active areas on ACWNS that exhibit a degree of specificity for the individual ions. Results obtained from real water sample analysis confirmed ACWNS as highly efficient to be utilized for practical remediation processes.
水体中新兴污染物（如 PO 和 NO）的存在引起了全世界对其对水体和人类健康的严重影响的关注。因此，为了保护人类健康和环境安全，在将工业废水排放到水体之前对其进行处理至关重要。合成、表征了胺功能化核桃壳（ACWNS），并将其作为一种新型吸附剂来去除 PO 和 NO。研究了 pH、剂量、初始磷酸盐浓度、干扰离子和温度对磷酸盐和硝酸盐去除的影响。值得注意的是，PO 和 NO 的吸附是放热和自发的，在 293 K 时，磷酸盐和硝酸盐的最大吸附容量分别为 82.2 和 35.7 mg g。这些离子被吸附到 ACWNS 上的机制可能是静电相互作用和氢键。伪二阶动力学模型拟合了 PO 和 NO 的吸附，而 Freundlich 和 Langmuir 模型分别拟合了 PO 和 NO 的吸附。此外，在二元体系中，磷酸盐的吸附容量降低了 14.4%，而硝酸盐的吸附容量降低了 10.4%。ACWNS 对两种离子都有更高的吸引力，这可能是由于 ACWNS 上存在多种活性区域，对各离子表现出一定的特异性。实际水样分析结果证实，ACWNS 非常高效，可用于实际修复过程。
