Dye-containing industrial effluents create major concern nowadays. To address the problem, magnetic nickel oxide nanoparticles (NONPs) were synthesized using the autopropagator combustion technique assisted by sucrose as fuel and used for the removal of toxic malachite green (MG) from water. The material was characterized by scanning electron microscopy (SEM–EDS), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating sample magnetism (VSM), point of zero charge (pH_ZPC), and Brunauer–Emmet–Teller surface area analysis. SEM images show flowerlike texture with the presence of multiple pores. VSM reveals a well-defined hysteresis at room temperature, confirming a permanent magnetic nature of the material. pH_ZPC was found to be 6.63, which enables dye separation in the drinking water pH range. MG removal from water was carried out in the batch mode with optimized physicochemical parameters such as contact time, pH, temperature, and dose. Langmuir adsorption capacity was estimated to be 87.72 mg/g. Pseudo-second order kinetics (R² = 0.999) and Langmuir isotherm model (R² = 0.997) were found to best fit. The magnetic nature facilitates fast and quantitative separation of NONPs from solution using a hand-held magnet. Dye-loaded NONPs can be easily regenerated up to 89% and reused up to five cycles without significant loss of activity. The mechanism of adsorption is proposed to be a combination of electrostatic attraction and weak hydrogen bonding. Strategically designed straightforward synthetic protocol, low cost, high uptake capacity, and sustainable use render NONPs an ideal alternative for future dye treatment.

中文翻译：

---

蔗糖触发的，自持的磁性氧化镍纳米粒子的燃烧合成以及从水中的高效去除孔雀石绿。

如今，含染料的工业废水备受关注。为了解决该问题，使用以蔗糖为燃料的自动传播燃烧技术合成了磁性氧化镍纳米粒子（NONPs），并用于从水中去除有毒的孔雀石绿（MG）。通过扫描电子显微镜（SEM-EDS），傅立叶变换红外光谱（FTIR），X射线衍射（XRD），振动样品磁化（VSM），零电荷点（pH _ZPC）和Brunauer- Emmet-Teller表面积分析。SEM图像显示具有多个孔的花朵状纹理。VSM在室温下显示出明确的磁滞现象，从而确认了材料的永久磁性。pH _ZPC被发现为6.63，可以在饮用水pH范围内分离染料。以最佳的物理化学参数（例如接触时间，pH，温度和剂量）以分批模式从水中去除MG。朗格缪尔的吸附容量估计为87.72 mg / g。伪二级动力学（R ² = 0.999）和Langmuir等温模型（R ²= 0.997）被认为是最合适的。磁性有助于使用手持磁铁从溶液中快速定量分离NONP。染有染料的NONP可以轻松再生高达89％，并可以重复使用多达5个循环，而不会显着降低活性。吸附机理被认为是静电吸引和弱氢键的结合。具有战略意义的简单合成方案，低成本，高吸收能力和可持续使用使NONPs成为未来染料处理的理想选择。