Department of Chemistry, Jamia Millia Islamia (Central University), Jamia Nagar, New Delhi 110025, India.
Department of Chemistry, King Abdulaziz University, Jeddah 22254, Saudi Arabia.
Molecules. 2022 Aug 31;27(17):5623. doi: 10.3390/molecules27175623.
A novel polyaniline-modified CNT and graphene-based nanocomposite (2.32-7.34 nm) was prepared and characterized by spectroscopic methods. The specific surface area was 176 m/g with 0.232 cm/g as the specific pore volume. The nanocomposite was used to remove zinc and lead metal ions from water; showing a high removal capacity of 346 and 581 mg/g at pH 6.5. The data followed pseudo-second-order, intraparticle diffusion and Elovich models. Besides this, the experimental values obeyed Langmuir and Temkin isotherms. The results confirmed that the removal of lead and zinc ions occurred in a mixed mode, that is, diffusion absorption and ion exchange between the heterogeneous surface of the sorbent containing active adsorption centers and the solution containing metal ions. The enthalpy values were 149.9 and 158.6 J.molK for zinc and lead metal ions. The negative values of free energies were in the range of -4.97 to -26.3 kJ/mol. These values indicated an endothermic spontaneous removal of metal ions from water. The reported method is useful to remove the zinc and lead metal ions in any water body due to the high removal capacity of nanocomposite at natural pH of 6.5. Moreover, a low dose of 0.005 g per 30 mL made this method economical. Furthermore, a low contact time of 15 min made this method applicable to the removal of the reported metal ions from water in a short time. Briefly, the reported method is highly economical, nature-friendly and fast and can be used to remove the reported metal ions from any water resource.
一种新型的聚酰亚胺修饰的 CNT 和基于石墨烯的纳米复合材料（2.32-7.34nm）被制备并通过光谱方法进行了表征。比表面积为 176m/g，比孔体积为 0.232cm/g。该纳米复合材料被用于从水中去除锌和铅金属离子；在 pH6.5 时，表现出 346 和 581mg/g 的高去除容量。数据符合准二级、内扩散和 Elovich 模型。此外，实验值符合 Langmuir 和 Temkin 等温线。结果证实，铅和锌离子的去除以混合模式发生，即在含有活性吸附中心的异质表面和含有金属离子的溶液之间的扩散吸收和离子交换。焓值分别为锌和铅金属离子的 149.9 和 158.6J/mol。自由能的负值在-4.97 到-26.3kJ/mol 范围内。这些值表明从水中自发地去除金属离子是吸热的。由于纳米复合材料在自然 pH 值 6.5 下具有高去除容量，因此该方法可用于去除任何水体中的锌和铅金属离子。此外，低剂量为 0.005g/30mL，使该方法具有经济性。此外，低接触时间为 15min，使得该方法适用于在短时间内从水中去除所报道的金属离子。简而言之，所报道的方法具有高度的经济性、环境友好性和快速性，可以用于从任何水资源中去除所报道的金属离子。
