College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China.
College of Environmental Science and Engineering, Hunan University, Changsha 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, China.
Bioresour Technol. 2021 Feb;321:124413. doi: 10.1016/j.biortech.2020.124413. Epub 2020 Nov 16.
This study prepared sewage sludge, a municipal solid waste, into a biochar modified by hydroxyapatite (HAP) as a new and efficient absorbent (HAP-SSBC) for removal of Cu and Cd from aqueous solution. Adsorption experiment revealed that HAP-SSBC exhibited significantly higher adsorption performance than raw sludge-based biochar (SSBC). At 298.15 K, the maximum adsorption capacity of Cu and Cd via Langmuir model were 89.98 and 114.68 mg/g, respectively. Adsorption kinetic experiment revealed that chemisorption was the main reaction. Analysis of X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectrum (XPS) further confirmed that the main mechanisms were ion exchange with Ca, complexion by -OH and -COOH, and forming Cu-π or Cd-π binding with aromatic CC on HAP-SSBC surface. Overall, combing HAP and SSBC to be a new adsorbent is beneficial to the resource utilization of sludge and shows a good prospect for heavy metal removal in aqueous solution.
本研究将市政固体废物污水污泥制备成羟基磷灰石（HAP）改性生物炭（HAP-SSBC），作为一种从水溶液中去除 Cu 和 Cd 的新型高效吸附剂。吸附实验表明，HAP-SSBC 的吸附性能明显高于原始污泥基生物炭（SSBC）。在 298.15 K 下，通过 Langmuir 模型计算出 Cu 和 Cd 的最大吸附容量分别为 89.98 和 114.68 mg/g。吸附动力学实验表明，化学吸附是主要反应。X 射线衍射（XRD）、傅里叶变换红外（FT-IR）光谱和 X 射线光电子能谱（XPS）分析进一步证实，主要机制是与 Ca 的离子交换、-OH 和 -COOH 的络合，以及在 HAP-SSBC 表面形成 Cu-π 或 Cd-π 键与芳族 CC。总的来说，将 HAP 和 SSBC 结合起来作为一种新型吸附剂有利于污泥的资源化利用，在水溶液中去除重金属方面具有良好的应用前景。
