State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
School of Engineering, South China Agriculture University, Guangzhou 510642, China.
Sci Total Environ. 2019 Feb 25;653:64-73. doi: 10.1016/j.scitotenv.2018.10.331. Epub 2018 Oct 26.
This study originally investigated the selective adsorption of cyclic organics in APCPW by LAC, corresponding to the change of the bioavailability. As a product from low rank coal, LAC showed more oxygen (O)-containing groups and mesoporous structure than PAC. Adsorption mechanisms were analyzed by equilibrium isotherms and kinetics models combined with physicochemical properties of adsorbent and adsorbates. The results indicated that selectivity of LAC was dominated by chemical interaction and its mesoporous, and was enhanced by hydrophobicity of adsorbates. In addition, PAC and LAC were applied for the treatment of APCPW. Compared with PAC, LAC adsorption exhibited superior removal efficiency of Tph, TOC and TN at 85.90%, 91.15% and 51.64%, respectively. Furthermore, preferential adsorption of biotoxic and bioresistant cyclic organics by LAC was further proved by GC-MS analysis, resulting in increased bioavailability of APCPW. Specifically, LAC exerted sustained detoxication capacity until 86.50% reduction of TU by D. magna evaluation, and lowered toxicity rank (TU = 4.51, classIII) to T. pyriformis than that after PAC adsorption (TU > 10, ClassIV). Meanwhile, biodegradability was also improved by 9.17% after LAC adsorption. Lastly, LAC would exhibit great economic benefits as an alternative for PAC in subsequent process after anaerobic pretreatment.
本研究最初考察了 LAC 对 APCPW 中环状有机物的选择性吸附，这与生物可利用性的变化相对应。作为低阶煤的产物，LAC 比 PAC 具有更多的含氧（O）基团和中孔结构。通过平衡等温线和动力学模型，并结合吸附剂和吸附质的物理化学性质，分析了吸附机制。结果表明，LAC 的选择性主要由化学相互作用和其中孔结构决定，并通过吸附质的疏水性得到增强。此外，PAC 和 LAC 被应用于 APCPW 的处理。与 PAC 相比，LAC 吸附对 Tph、TOC 和 TN 的去除效率分别提高了 85.90%、91.15%和 51.64%。此外，通过 GC-MS 分析进一步证明了 LAC 对生物毒性和生物抗性环状有机物的优先吸附，从而提高了 APCPW 的生物可利用性。具体而言，LAC 发挥了持续的解毒能力，直到用 D. magna 评价时 TU 减少了 86.50%，并将毒性等级（TU=4.51，III 类）降低到比 PAC 吸附后（TU>10，IV 类）更低的水平。同时，生物降解性也提高了 9.17%。最后，LAC 在厌氧预处理后的后续过程中作为 PAC 的替代物，将具有很大的经济效益。
