High-density polyethylene (HDPE) waste and chicken eggshell were used to synthesize three novel adsorbents, namely mesoporous graphene (MG), nano-eggshell modified graphene (nEMG), and nano-magnetic eggshell modified graphene (nM-EMG) for methyl red (MR) adsorption from simulated wastewater. The effects of adsorption conditions (pH, contact time, initial dye concentration, adsorbent dose, and temperature) were investigated. MG, nEMG, and nM-EMG were characterized using SEM, TEM, BET, EDX, XRD, and FTIR analyses. MG, nEMG, and nM-EMG had specific surface areas of 15, 31, and 179 m²/g and mean pore diameters of 27, 29, and 5 nm respectively. The equilibrium adsorption capacities of MG, nEMG, and nM-EMG were 5.6, 8.1, and 6.5 mg/g respectively at MR concentration of 100 mg/L, pH 4, adsorbent dose of 1.0 g/100 mL, and temperature of 25 °C. All MR sorption processes followed the pseudo-second-order and Langmuir–Freundlich model. The adsorption rates were controlled by intra-particle and film diffusion. MR uptake on the synthesized adsorbents was spontaneous, endothermic, and chemisorption. The adsorption occurred via electrostatic interactions, π electron interactions, and hydrogen bonding. The performance of the prepared adsorbents was examined in different water matrices and compared with other MR adsorbents. After five regeneration cycles, the adsorbent reusability study showed that nM-EMG is the most stable and reusable adsorbent.

高密度聚乙烯（HDPE）废料和鸡蛋壳用于合成三种新型吸附剂，即介孔石墨烯（MG）、纳米蛋壳改性石墨烯（nEMG）和纳米磁性蛋壳改性石墨烯（nM-EMG）用于甲基红(MR) 从模拟废水中吸附。研究了吸附条件（pH、接触时间、初始染料浓度、吸附剂剂量和温度）的影响。使用 SEM、TEM、BET、EDX、XRD 和 FTIR 分析对 MG、nEMG 和 nM-EMG 进行了表征。MG、nEMG 和 nM-EMG 的比表面积分别为 15、31 和 179 m ²/g 和平均孔径分别为 27、29 和 5 nm。在 MR 浓度 100 mg/L、pH 4、吸附剂量 1.0 g/100 mL、温度 25 °C 时，MG、nEMG 和 nM-EMG 的平衡吸附容量分别为 5.6、8.1 和 6.5 mg/g C。所有 MR 吸附过程都遵循准二级和 Langmuir-Freundlich 模型。吸附速率由颗粒内扩散和膜扩散控制。合成吸附剂上的 MR 吸收是自发的、吸热的和化学吸附的。吸附通过静电相互作用、π电子相互作用和氢键发生。在不同的水基质中检查了制备的吸附剂的性能，并与其他 MR 吸附剂进行了比较。五次再生循环后，