Mehrabi Novin, Masud Arvid, Afolabi Moyosore, Hwang Jinwoo, Calderon Ortiz Gabriel A, Aich Nirupam
Department of Civil, Structural and Environmental Engineering, University at Buffalo, The State University of New York Buffalo NY 14260 USA
School of Civil and Environmental Engineering, Georgia Institute of Technology Atlanta GA 30332 USA.
RSC Adv. 2019 Jan 8;9(2):963-973. doi: 10.1039/c8ra08386j. eCollection 2019 Jan 2.
GO and nZVI have been used for removing different contaminants from aqueous solution; however, difficulty in the separation of GO, and the aggregation propensity of nZVI particles prevent them from having efficient practical applications. In this study, a green synthesis method was performed to prepare nanohybrids of GO and nZVI to provide an adsorbent with high adsorption efficiency that can be removed from aqueous solution easily by magnetic separation. GO-nZVI nanohybrids were synthesized by using biocompatible cross linkers named 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) and -hydroxysuccinimide (NHS). The effect of the nZVI ratio in the synthesized nanohybrids was studied at three different ratios of GO : nZVI, 1 : 1, 1 : 5 and 1 : 10. SEM/EDS, HRTEM, STEM/EDS, XRD, Raman, FTIR, and TGA analyses were conducted to provide physical and chemical properties of the adsorbents. The performance of nZVI and GO-nZVI nanohybrids as an adsorbent have been studied for methylene blue (MB) removal from an aqueous solution with an initial concentration of 12 mg L at adsorbent dosages of 0.1, 0.3, 0.5, and 1 mg mL. Results indicated that GO-nZVI (1 : 5) provided the highest MB removal (99.1%) by using 10 mL of the 1 mg mL adsorbent. After regeneration of the GO-nZVI (1 : 5) nanohybrids with ethanol, 84.3%, 67.2%, and 63.0% of MB removal were achieved in the first to third regeneration cycle. Results also showed that the GO-nZVI nanohybrids were not affected by aggregation compared to nZVI.
氧化石墨烯（GO）和纳米零价铁（nZVI）已被用于去除水溶液中的不同污染物；然而，GO分离困难以及nZVI颗粒的聚集倾向阻碍了它们的高效实际应用。在本研究中，采用绿色合成方法制备了GO和nZVI的纳米杂化物，以提供一种具有高吸附效率的吸附剂，该吸附剂可通过磁分离轻松地从水溶液中去除。使用名为1-乙基-3-(3-二甲基氨基丙基)-碳二亚胺（EDC）和N-羟基琥珀酰亚胺（NHS）的生物相容性交联剂合成了GO-nZVI纳米杂化物。研究了合成的纳米杂化物中nZVI比例在三种不同的GO:nZVI比例（1:1、1:5和1:10）下的影响。进行了扫描电子显微镜/能谱（SEM/EDS）、高分辨率透射电子显微镜（HRTEM）、扫描透射电子显微镜/能谱（STEM/EDS）、X射线衍射（XRD）、拉曼光谱、傅里叶变换红外光谱（FTIR）和热重分析（TGA），以提供吸附剂的物理和化学性质。研究了nZVI和GO-nZVI纳米杂化物作为吸附剂在初始浓度为12 mg/L的水溶液中去除亚甲基蓝（MB）的性能，吸附剂剂量分别为0.1、0.3、0.5和1 mg/mL。结果表明，使用10 mL 1 mg/mL的吸附剂时，GO-nZVI（1:5）对MB的去除率最高（99.1%）。用乙醇对GO-nZVI（1:5）纳米杂化物进行再生后，在第一至第三个再生循环中，MB的去除率分别达到84.3%、67.2%和63.0%。结果还表明，与nZVI相比，GO-nZVI纳米杂化物不受聚集的影响。
