Bharath G, Rambabu K, Banat Fawzi, Hai Abdul, Arangadi Abdul Fahim, Ponpandian N
Department of Chemical Engineering, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi, United Arab Emirates.
Department of Chemical Engineering, Khalifa University of Science and Technology, P.O. Box 127788, Abu Dhabi, United Arab Emirates.
Sci Total Environ. 2019 Nov 15;691:713-726. doi: 10.1016/j.scitotenv.2019.07.069. Epub 2019 Jul 6.
Capacitive deionization (CDI) is one of the most efficient and emerging techniques for the removal of toxic metal ions from aqueous solutions. In this study, mesoporous peanut shell derived activated carbon (PSAC) was prepared by low temperature pyrolysis at 500 °C. Subsequently, a novel iron oxide/PSAC (FeO/PSAC) nanocomposite adsorbent was prepared via facile one-pot hydrothermal synthesis method at 180 °C. Nucleation growth mechanism and appropriate characterizations of prepared nanocomposites were investigated. The obtained FeO/PSAC possessed a highly mesoporous structure, and a large specific surface area (680 m/g). The electrochemical analysis showed that the obtained FeO/PSAC nanocomposites exhibited higher capacitance (610 F/g at 10 mV/s), good stability and low internal resistance. A batch mode adsorption and CDI based Cr(VI) removal studies were conducted. Effects of solution pH and cycle time on Cr(VI) electrosorption capacity were further investigated. The FeO/PSAC based electrodes exhibit a maximum electrosorption capacity of 24.5 mg/g at 1.2 V, which was remarkably larger than other reported materials. The fabricated composite displayed higher electrosorption capacity with rapid time and a favorable reduction of Cr (VI) to Cr(III). Studies indicated that the FeO/PSAC based CDI electrode possesses a good potential to be applied for the removal of toxic metal ions from wastewater.
电容去离子化（CDI）是从水溶液中去除有毒金属离子最有效且新兴的技术之一。在本研究中，通过在500℃下低温热解制备了介孔花生壳衍生的活性炭（PSAC）。随后，通过在180℃下简便的一锅水热合成法制备了一种新型的氧化铁/PSAC（FeO/PSAC）纳米复合吸附剂。研究了制备的纳米复合材料的成核生长机理和适当的表征。所获得的FeO/PSAC具有高度介孔结构和大的比表面积（680 m/g）。电化学分析表明，所获得的FeO/PSAC纳米复合材料表现出更高的电容（在10 mV/s时为610 F/g）、良好的稳定性和低内阻。进行了基于分批模式吸附和CDI的Cr(VI)去除研究。进一步研究了溶液pH值和循环时间对Cr(VI)电吸附容量的影响。基于FeO/PSAC的电极在1.2 V时表现出最大电吸附容量为24.5 mg/g，这明显大于其他报道的材料。所制备的复合材料显示出更高的电吸附容量且时间快速，并且Cr(VI)向Cr(III)有良好的还原。研究表明，基于FeO/PSAC的CDI电极具有从废水中去除有毒金属离子的良好应用潜力。
