Department of Environmental Science & Engineering, Hunan Agricultural University, Changsha, People's Republic of China.
Laboratory of Environmental Microbiology and Toxicology, School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, People's Republic of China.
Environ Technol. 2020 Jan;41(3):357-365. doi: 10.1080/09593330.2018.1498922. Epub 2018 Jul 27.
The Mg/Al layered double hydroxide (Mg/Al-LDH) intercalated with the [Formula: see text] (MoS-LDH) impregnated into poly(acrylamide-co-sodium acrylate) (PP) was synthesized as layered double hydroxides-PP (LDHS-PP), whose characterization, adsorption properties and mechanisms were investigated. The maximum adsorption capacity () for Cd(II) was ∼2789.58 mg/g by 1% LDHS-PP, while it was ∼1893.09 mg/g by PP, which indicated that the MoS-LDH greatly improved the Cd(II) uptake for PP in aqueous solution. In strongly acidic conditions (∼pH 3.0), there was still a good removal efficiency of about 45.65% by the 1% LDHS-PP, while that of PP was almost zero. At pH 5.0 the removal efficiency increased to 85.17% by the 1% LDHS-PP. The sorption kinetics for the 1% LDHS-PP was described well by a pseudo-second-order kinetic model. X-ray photoelectron spectrometry (XPS) and elemental distribution maps further confirmed the presence of MoS-LDH in the PP and most of the Cd(II) chemisorption based on the Cd-S bonding. Due to its high removal efficiency and acid resistance, LDHS-PP is a promising in-situ fixation agent for the remediation of agricultural soil polluted with Cd(II) at low pH.
镁/铝层状双氢氧化物（Mg/Al-LDH）插层的[化学式：见正文]（MoS-LDH）浸渍到聚丙烯酰胺-丙烯酸钠共聚物（PP）中，合成了层状双氢氧化物-PP（LDHS-PP），对其进行了表征、吸附性能和机制研究。1% LDHS-PP 对 Cd(II)的最大吸附容量约为 2789.58 mg/g，而 PP 的最大吸附容量约为 1893.09 mg/g，这表明 MoS-LDH 大大提高了 PP 在水溶液中对 Cd(II)的吸附能力。在强酸性条件（约 pH 3.0）下，1% LDHS-PP 的去除效率仍约为 45.65%，而 PP 的去除效率几乎为零。在 pH 5.0 时，1% LDHS-PP 的去除效率增加到 85.17%。1% LDHS-PP 的吸附动力学很好地符合准二级动力学模型。X 射线光电子能谱（XPS）和元素分布图谱进一步证实了 MoS-LDH 存在于 PP 中，并且大部分 Cd(II)是基于 Cd-S 键合的化学吸附。由于其高去除效率和耐酸性，LDHS-PP 是一种很有前途的原位固定剂，可用于修复低 pH 条件下农业土壤中 Cd(II)污染。
