Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China; State Key Laboratory of Black Soils Conservation and Utilization, Changchun, 130102, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China; State Key Laboratory of Black Soils Conservation and Utilization, Changchun, 130102, China.
Chemosphere. 2023 Oct;339:139764. doi: 10.1016/j.chemosphere.2023.139764. Epub 2023 Aug 7.
Research studies have modified traditional substances to seek fast-acting removal of phosphorus in constructed wetlands (CWs) and ecological dams, rather than develop a brand-new nano-adsorbent. This work synthesized FeCa-based layered double hydroxide (FeCa-LDH) with a chemical co-precipitation method, and the performance, mechanism and factors of phosphorus removal were investigated. FeCa-LDH showed a marked ability to adsorb phosphorus from waste water, with a removal efficiency of 94.4% and 98.2% in CWs and ecological dams, respectively. Both FTIR and XPS spectrum evidenced that FeCa-LDH removed phosphorus via electrostatic and hydrogen-bonding adsorption, as well as a coordination reaction and interlayer anion exchange. FeCa-LDH showed a higher capacity to remove phosphorus in alkaline and neutral waste water than in acid conditions. Co-occurrence anions, which influenced the efficiency of the phosphorus removal capacity are considered in the sequence below: CO ≈ HCO > SO > NO. Innovatively, FeCa-LDH was not affected by the low-temperature limitation for CWs, and phosphorus removal efficiency at 5 °C was almost equal to that at 25 °C. These results cast a new idea on the construction, application and phosphorus removal performance of CWs and ecological dams.
研究人员对传统物质进行了改良，以寻求在人工湿地（CWs）和生态坝中快速去除磷，而不是开发全新的纳米吸附剂。本工作采用化学共沉淀法合成了基于 FeCa 的层状双氢氧化物（FeCa-LDH），并对其磷去除性能、机制和影响因素进行了研究。FeCa-LDH 对废水中的磷具有明显的吸附能力，在 CWs 和生态坝中的去除效率分别达到 94.4%和 98.2%。FTIR 和 XPS 谱图表明，FeCa-LDH 通过静电和氢键吸附、配位反应和层间阴离子交换去除磷。FeCa-LDH 在碱性和中性废水中的磷去除容量高于酸性条件。共存阴离子对磷去除效率的影响顺序如下：CO≈HCO>SO>NO。创新性地，FeCa-LDH 不受 CWs 低温限制的影响，5°C 时的磷去除效率几乎与 25°C 时相同。这些结果为 CWs 和生态坝的构建、应用和磷去除性能提供了新的思路。
