College of Land Science and Technology, China Agricultural University, Beijing, People's Republic of China.
School of Environment, Tsinghua University, Beijing, People's Republic of China.
Environ Technol. 2022 Nov;43(27):4269-4278. doi: 10.1080/09593330.2021.1946597. Epub 2021 Jul 22.
In this study, we synthesised metakaolin-based mesoporous geopolymer adsorbent and investigated the effect of alkaline activator modulus (molar ratios of SiO/NaO) on Pb adsorption. The geopolymer prepared using 1.2 M alkaline activator performs excellent Pb removal with a maximum adsorption capacity of 172.71 mg g. The pseudo-second-order model fit the adsorption kinetics satisfactorily, indicating that the adsorption process is dominated by chemical adsorption. The adsorption data appropriately fit the Langmuir isotherm model. The contributions of adsorption methods corresponding to the total quantity adsorbed declined in the following order: EDTA extraction (formation of Pb aluminium oxide and Pb-containing amorphous materials) > residual fraction (Pb stabilisation in the tetrahedral aluminosilicate network) > ion exchange. Overall, the alkaline activator modulus significantly influenced the Pb adsorption characteristics of the geopolymer adsorbent.
在这项研究中，我们合成了基于偏高岭土的中孔地质聚合物吸附剂，并研究了碱性激发剂模数（SiO/NaO 的摩尔比）对 Pb 吸附的影响。使用 1.2 M 碱性激发剂制备的地质聚合物对 Pb 的去除效果非常好，最大吸附容量为 172.71mg g。准二级动力学模型很好地拟合了吸附动力学，表明吸附过程主要是化学吸附。吸附数据很好地拟合了 Langmuir 等温模型。对应于总吸附量的吸附方法的贡献按以下顺序降低：EDTA 提取（形成 Pb 铝氧化物和含 Pb 的无定形材料）>残余分数（Pb 在四面体型铝硅酸盐网络中的稳定化）>离子交换。总的来说，碱性激发剂模数显著影响了地质聚合物吸附剂对 Pb 的吸附特性。
