Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
J Environ Sci (China). 2019 Nov;85:168-176. doi: 10.1016/j.jes.2019.06.004. Epub 2019 Jun 12.
Cadmium (Cd) and arsenic (As) are two of the most toxic elements. However, the chemical behaviors of these two elements are different, making it challenging to utilize a single adsorbent with high adsorption capacity for both Cd(II) and As(V) removal. To solve this problem, we synthesized HA/Fe-Mn oxides-loaded biochar (HFMB), a novel ternary material, to perform this task, wherein scanning electron microscopy (SEM) combined with EDS (SEM-EDS) was used to characterize its morphological and physicochemical properties. The maximum adsorption capacity of HFMB was 67.11 mg/g for Cd(II) and 35.59 mg/g for As(V), which is much higher compared to pristine biochar (11.06 mg/g, 0 mg/g for Cd(II) and As(V), respectively). The adsorption characteristics were investigated by adsorption kinetics and the effects of the ionic strength and pH of solutions. X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR) revealed that chelation and deposition were the adsorption mechanisms that bound Cd(II) to HFMB, while ligand exchange was the adsorption mechanism that bound As(V).
镉（Cd）和砷（As）是两种毒性最大的元素。然而，这两种元素的化学行为不同，因此很难利用单一吸附剂同时具有高吸附容量，以去除 Cd(II) 和 As(V)。为了解决这个问题，我们合成了一种新型的三组分材料，即负载 HA/Fe-Mn 氧化物的生物炭（HFMB），并用扫描电子显微镜（SEM）结合能谱仪（SEM-EDS）对其形态和物理化学性质进行了表征。HFMB 对 Cd(II) 的最大吸附容量为 67.11 mg/g，对 As(V) 的最大吸附容量为 35.59 mg/g，明显高于原始生物炭（分别为 11.06 mg/g 和 0 mg/g）。通过吸附动力学和溶液离子强度及 pH 值的影响研究了吸附特性。X 射线光电子能谱（XPS）和傅里叶变换红外光谱（FT-IR）表明，螯合和沉淀是将 Cd(II) 与 HFMB 结合的吸附机制，而配体交换则是将 As(V) 与 HFMB 结合的吸附机制。
