Li Hangyu, Cui Shihao, Tan Yi, Peng Yutao, Gao Xing, Yang Xiao, Ma Yan, He Xinyue, Fan Beibei, Yang Sen, Chen Qing
Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China; Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China.
Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China.
Environ Pollut. 2022 Feb 1;294:118592. doi: 10.1016/j.envpol.2021.118592. Epub 2021 Nov 29.
Although biochar supports were widely adopted to fabricate the biochar (BC) supported layered double hydroxides (LDHs) composites (LDH-BC) for efficient environmental remediation, few studies focus on the important role of biochar support in alleviating the stacking of LDHs and enhancing LDH-BC's performance. Through the analysis of the material structure-performance relationship, the "support effect" of fine biochar prepared by ball milling was carefully explored. Compared with the original LDHs on LDH-BC, the LDHs on ball milled biochar (LDH-BMBC) had smaller particle size (from 1123 nm to 586 nm), crystallite size (from 20.5 nm to 6.56 nm), more abundant O-containing functional groups, and larger surface area (370 m g) and porous structure. The Langmuir model revealed that the maximum theoretical phosphate adsorption capacity of LDH-BMBC (56.2 mg P g) was significantly higher than that of LDH-BC (27.6 mg P g). The leaching experiment proved that the addition of LDH-BMBC in calcareous soil could significantly reduce the release of soil total phosphate (46.1%) and molybdate reactive phosphate (40.4%), even though pristine BC and BMBC significantly enhanced the soil phosphate leaching. This work fabricated high-performance and eco-friendly LDH-BMBC for phosphate adsorption in solution and phosphate retention in soil and also provide valuable insights into fine biochar support effect on LDHs exfoliation, extending the practical use of the engineered ball milled biochars in environment remediation.
尽管生物炭载体被广泛用于制备生物炭（BC）负载的层状双氢氧化物（LDHs）复合材料（LDH-BC）以实现高效的环境修复，但很少有研究关注生物炭载体在缓解LDHs堆积和提高LDH-BC性能方面的重要作用。通过对材料结构-性能关系的分析，仔细探究了球磨制备的精细生物炭的“载体效应”。与LDH-BC上的原始LDHs相比，球磨生物炭上的LDHs（LDH-BMBC）具有更小的粒径（从1123 nm降至586 nm）、微晶尺寸（从20.5 nm降至6.56 nm）、更丰富的含O官能团、更大的表面积（370 m²/g）和多孔结构。Langmuir模型表明，LDH-BMBC的最大理论磷酸盐吸附容量（56.2 mg P/g）显著高于LDH-BC（27.6 mg P/g）。浸出实验证明，在石灰性土壤中添加LDH-BMBC可显著降低土壤总磷（46.1%）和钼酸反应性磷（40.4%）的释放，尽管原始BC和BMBC显著增强了土壤磷的淋溶。这项工作制备了用于溶液中磷酸盐吸附和土壤中磷酸盐保留的高性能且环保的LDH-BMBC，还为精细生物炭对LDHs剥离的载体效应提供了有价值的见解，扩展了工程化球磨生物炭在环境修复中的实际应用。
