Department of Environmental Engineering, Graduate Faculty of Environment, University of Tehran, Iran.
Department of Food Science & Technology, Faculty of Agricultural Engineering and Technology, University of Tehran, Karaj, Iran; Food Technology and Agricultural Products Research Center, Standard Research Institute (SRI), Karaj, Iran.
Environ Res. 2023 Jan 1;216(Pt 1):114416. doi: 10.1016/j.envres.2022.114416. Epub 2022 Sep 28.
In this study, an adsorbent made of alginate (Alg) caged magnesium sulfide nanoparticles (MgS) microbeads were used to treat lead ions (Pb ions). The MgS nanoparticles were synthesized at low temperatures, and Alg@MgS hydrogel microbeads were made by the ion exchange process of the composite materials. The newly fabricated Alg@MgS was characterized by XRD, SEM, and FT-IR. The adsorption conditions were optimized for the maximum removal of Pb ions by adjusting several physicochemical parameters, including pH, initial concentration of lead ions, Alg/MgS dosage, reaction temperature, equilibration time, and the presence of co-ions. This is accomplished by removing the maximum amount of Pb ions. Moreover, the adsorbent utilized more than six times with a substantial amount (not less than 60%) of Pb ions was eliminated. Considering the ability of sodium alginate (SA) for excellent metal chelation and controlled nanosized pore structure, the adsorption equilibrium of Alg@MgS can be reached in 60 min, and the highest adsorption capacity for Pb was 84.7 mg/g. The sorption mechanism was explored by employing several isotherms. It was found that the Freundlich model fits the adsorption process quite accurately. The pseudo-second-order model adequately described the adsorption kinetics.
在这项研究中，使用了一种由海藻酸钠（Alg）笼状硫酸镁纳米粒子（MgS）微球制成的吸附剂来处理铅离子（Pb 离子）。MgS 纳米粒子在低温下合成，通过复合材料的离子交换过程制得 Alg@MgS 水凝胶微球。新制备的 Alg@MgS 通过 XRD、SEM 和 FT-IR 进行了表征。通过调整几个物理化学参数，包括 pH、铅离子的初始浓度、Alg/MgS 剂量、反应温度、平衡时间和共存离子，优化了吸附条件，以实现最大的 Pb 离子去除。这是通过去除最大量的 Pb 离子来完成的。此外，该吸附剂可以重复使用六次以上，并且可以去除大量（不少于 60%）的 Pb 离子。考虑到海藻酸钠（SA）具有良好的金属螯合能力和可控的纳米级孔结构，Alg@MgS 的吸附平衡可以在 60 分钟内达到，对 Pb 的最高吸附容量为 84.7mg/g。通过使用几种等温线研究了吸附机理。结果表明，Freundlich 模型非常准确地描述了吸附过程。准二级动力学模型很好地描述了吸附动力学。
