College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China.
College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China; Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha 410004, China.
Bioresour Technol. 2022 Oct;362:127851. doi: 10.1016/j.biortech.2022.127851. Epub 2022 Aug 27.
Development of an efficient and green adsorbent is of great significance for phosphorus removal and recovery from eutrophic water. This work prepared an eggshell modified biochar (ESBC) by co-pyrolysis of eggshells and corn stalk. ESBC exhibited an excellent performance for phosphorus adsorption over a wide pH range (5-13), and achieved a maximum adsorption of 557.0 mg P/g. The adsorption process was well fitted by pseudo-second-order model (R > 0.962) and Sips model (R > 0.965), and it was endothermic (ΔH > 0) and spontaneous (ΔG < 0) according to thermodynamic analysis. The column experiment confirmed the feasibility of ESBC as a filter media for phosphorus removal in flow condition, and obtained a P removal of 460.0 mg/g. Soil burial tests indicated P-laden ESBC has a good P slow-release performance (maintained for up to 25 days). Overall, ESBC has a promising application potential as an efficient adsorbent for phosphorus recovery and subsequently as a slow-release fertilizer.
开发高效、环保的吸附剂对于从富营养化水中去除和回收磷具有重要意义。本工作通过蛋壳与玉米秸秆共热解制备了蛋壳改性生物炭（ESBC）。ESBC 在较宽的 pH 范围（5-13）内对磷表现出优异的吸附性能，最大吸附量达到 557.0 mg P/g。吸附过程较好地符合准二级动力学模型（R>0.962）和 Sips 模型（R>0.965），热力学分析表明该过程是吸热的（ΔH>0）和自发的（ΔG<0）。柱实验证实了 ESBC 作为流动条件下磷去除过滤介质的可行性，可获得 460.0 mg/g 的磷去除量。土壤掩埋试验表明，负载磷的 ESBC 具有良好的磷缓释性能（可维持长达 25 天）。总体而言，ESBC 作为一种高效的磷回收吸附剂，具有良好的应用前景，可随后作为缓释肥料。
