This study is aimed at studying the adsorption of methylene blue (MB) from aqueous solutions by nickel ferrite/graphene oxide (NGO) nanocomposite. The nanocomposite was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, energy dispersive X-ray, Brunauer-Emmett-Teller-specific surface area, and vibrating sample magnetometer analyses. The interactive effects of critical variables including pH, initial concentration, and contact time on the adsorption capacity of NGO for MB were studied using response surface methodology (RSM) according to composite central design. In RSM models, the predicted values agreed well with verification experiments, with a high correlation coefficient of 0.9887. The adsorption process followed the pseudo-second-order kinetic and Langmuir isotherm models. The maximum capacity for adsorption of MB onto NGO was found to be 476.19 mg/g. Based on these results, NGO has the potential as an efficient adsorbent for the removal of MB from water.

中文翻译：

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镍铁氧体-氧化石墨烯纳米复合材料吸附去除水中亚甲基蓝的制备及响应表面方法学

这项研究的目的是研究铁酸镍/氧化石墨烯（NGO）纳米复合材料从水溶液中吸附亚甲基蓝（MB）。通过傅里叶变换红外光谱，X射线衍射，X射线光电子能谱，透射电子显微镜，能量色散X射线，Brunauer-Emmett-Teller比表面积和振动样品磁强计分析对纳米复合材料进行了表征。根据复合中心设计，使用响应表面方法（RSM）研究了pH，初始浓度和接触时间等关键变量对NGO对MB的吸附能力的相互作用。在RSM模型中，预测值与验证实验非常吻合，具有0.9887的高相关系数。吸附过程遵循拟二级动力学和Langmuir等温模型。发现MB吸附在NGO上的最大容量为476.19 mg / g。基于这些结果，NGO具有作为从水中去除MB的有效吸附剂的潜力。