In this research, an eco-friendly magnetic adsorbent based on Fe₃O₄/salicylic acid nanocomposite was fabricated using a facile one-pot co-precipitation method. The crystalline and morphological characterization of the prepared nanocomposite was performed by field emission scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The nanocomposite was employed as a magnetic solid-phase extraction agent for separation of Cd(II) ions from synthetic solutions. Some experimental factors affecting the extraction efficiency were investigated and optimized. Following elution with acetic acid (pH 3.5), the preconcentrated analyte was quantified by flame atomic absorption spectrometry. In optimal conditions, a linear calibration graph was achieved in the concentration range of 0.2–30 ng·mL⁻¹ with a determination coefficient (R²) of 0.9953. The detection limit, the enhancement factor, inter- and intra-day relative standard deviations (for six consecutive extractions at the concentration level of 10 ng·mL⁻¹) were 0.04 ng·mL⁻¹, 100, 2.38% and 1.52%, respectively. To evaluate the accuracy of the method, a certified reference material (NIST SRM 1643e) was analyzed, and there was a good agreement between the certified and the measured values. It was successfully utilized to determine cadmium in industrial wastewater samples and the attained relative recovery values were between 96.8% and 103.2%.

在这项研究中，基于Fe ₃ O ₄的环保磁吸附剂唾液酸/水杨酸纳米复合材料是使用一种简便的一锅共沉淀法制备的。通过场发射扫描电子显微镜，X射线衍射和傅里叶变换红外光谱对所制备的纳米复合材料进行了结晶和形态表征。该纳米复合材料用作磁性固相萃取剂，用于从合成溶液中分离Cd（II）离子。研究和优化了影响萃取效率的一些实验因素。用乙酸（pH 3.5）洗脱后，通过火焰原子吸收光谱法对预浓缩的分析物进行定量。在最佳条件下，在0.2–30 ng·mL ^-1的浓度范围内获得线性校正图，并具有测定系数（R²）的0.9953。检测极限，增强因子，间和日内相对标准偏差（连续六个提取在10浓度水平纳克·ML ^-1）为0.04纳克·ML ^-1，100，2.38％和1.52％，分别。为了评估该方法的准确性，对经过认证的参考材料（NIST SRM 1643e）进行了分析，并且在认证值和测量值之间达成了良好的协议。该方法已成功用于工业废水样品中镉的测定，相对回收率在96.8％至103.2％之间。