ABSTRACT

A new adsorbent material based on graphene oxide (GO) functionalized with magnetic cobalt ferrite nanoparticles (γCoFe₂O₄) was synthesized via ultrasonication to remove the endocrine-disrupting-chemical bisphenol A (BPA) from aqueous solutions. The synthesized material (GO-γCoFe₂O₄) was characterized by TEM, SEM, DRX and FTIR analysis. Magnetization measures proved that the adsorbent had superparamagnetic characteristics that facilitated its separation from the aqueous solution. The maximum adsorption capacity obtained was 30 mg g⁻¹ with adsorbent concentration of 1 g L⁻¹, temperature of 55°C and natural pH of the solution. The experimental data were better adjusted to the kinetic models of pseudo-second-order and Langmuir isotherm. The thermodynamic parameters showed that the BPA adsorption on GO-γCoFe₂O₄ was spontaneous, exothermic and thermodynamically favourable. Desorption kinetics was performed using 50% ethanol as solvent, resulting in an equilibrium time of 4 h with better adjustment to the pseudo-second order kinetic model. The adsorbent showed a high regeneration capacity maintaining adsorptive capacity above 75% after 6 cycles of reuse.

摘要

_{通过超声处理合成了一种基于磁性钴铁氧体纳米颗粒（γCoFe 2} O ₄ ）功能化的氧化石墨烯（GO）的新型吸附材料，以去除水溶液中的内分泌干扰化学物质双酚A（BPA）。合成材料（GO-γCoFe ₂ O ₄）通过TEM、SEM、DRX和FTIR分析表征。磁化测量证明吸附剂具有超顺磁特性，有利于其从水溶液中分离。获得的最大吸附容量为 30 mg g ^-1，吸附剂浓度为 1 g L ^-1, 55°C 的温度和溶液的自然 pH 值。实验数据更好地适应准二级和朗缪尔等温线的动力学模型。热力学参数表明，GO-γCoFe ₂ O ₄上的 BPA 吸附是自发的、放热的和热力学有利的。使用 50% 乙醇作为溶剂进行解吸动力学，得到 4 小时的平衡时间，更好地调整到准二级动力学模型。该吸附剂显示出高再生能力，在重复使用 6 次后，吸附能力保持在 75% 以上。