Korea Biochar Research Center, APRU Sustainable Waste Management Program & Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea.
Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea.
J Hazard Mater. 2021 Aug 5;415:125464. doi: 10.1016/j.jhazmat.2021.125464. Epub 2021 Feb 19.
Excess phosphorous (P) in aquatic systems causes adverse environmental impacts including eutrophication. This study fabricated Fe(III) loaded chitosan-biochar composite fibers (FBC-N and FBC-C) from paper mill sludge biochar produced under N (BC-N) and CO (BC-C) conditions at 600 °C for adsorptive removal of phosphate from water. Investigations using SEM/EDX, XPS, Raman spectroscopy, and specific surface area measurement revealed the morphological and physico-chemical characteristics of the adsorbent. The Freundlich isotherm model well described the phosphate adsorption on BC-N, while the Redlich-Peterson model best fitted the data of three other adsorbents. The maximum adsorption capacities were 9.63, 8.56, 16.43, and 19.24 mg P g for BC-N, BC-C, FBC-N, and FBC-C, respectively, indicating better adsorption by Fe(III) loaded chitosan-biochar composite fibers (FBCs) than pristine biochars. The pseudo-first-order kinetic model suitably explained the phosphate adsorption on BC-C and BC-N, while data of FBC-N and FBC-C followed the pseudo-second-order and Elovich model, respectively. Molecular level observations of the P K-edge XANES spectra confirmed that phosphate associated with iron (Fe) minerals (Fe-P) were the primary species in all the adsorbents. This study suggests that FBCs hold high potential as inexpensive and green adsorbents for remediating phosphate in contaminated water, and encourage resource recovery via bio-based management of hazardous waste.
水体中过量的磷（P）会造成富营养化等不良环境影响。本研究以造纸厂污泥生物炭为原料，在 600°C 下分别在 N（BC-N）和 CO（BC-C）条件下制备了负载 Fe(III)的壳聚糖-生物炭复合纤维（FBC-N 和 FBC-C），用于从水中吸附去除磷酸盐。通过 SEM/EDX、XPS、拉曼光谱和比表面积测量等手段对吸附剂的形貌和物理化学特性进行了研究。Freundlich 等温模型很好地描述了磷酸盐在 BC-N 上的吸附，而 Redlich-Peterson 模型则很好地拟合了另外三种吸附剂的数据。BC-N、BC-C、FBC-N 和 FBC-C 的最大吸附容量分别为 9.63、8.56、16.43 和 19.24 mg P g，表明负载 Fe(III)的壳聚糖-生物炭复合纤维（FBCs）比原始生物炭具有更好的吸附性能。准一级动力学模型较好地解释了磷酸盐在 BC-C 和 BC-N 上的吸附，而 FBC-N 和 FBC-C 的数据分别遵循准二级和 Elovich 模型。P K-edge XANES 光谱的分子水平观察证实，与铁（Fe）矿物结合的磷酸盐（Fe-P）是所有吸附剂中的主要物种。本研究表明，FBCs 作为一种廉价且环保的吸附剂，具有修复受污染水中磷酸盐的巨大潜力，并通过对危险废物的生物基管理来促进资源回收。
