In this study, a simple and sensitive extraction method has been developed for preconcentration of trace amounts of cadmium ions using Kit-6 magnetite mesoporous nanocomposites (MMNCs) functionalized with sulfonic acid groups as adsorbent in solid phase extraction followed by flame atomic absorption spectrometry. For this purpose, the Kit-6 mesoporous silica was chemically synthesized on the surface of silica-coated magnetite core and functionalized by sulfonic acid groups to obtain Fe₃O₄@SiO₂@Kit-6-SO₃H. The synthesized nanocomposites were characterized by XRD, SEM, VSM and EDX methods. Various parameters affecting adsorption/desorption efficiencies were investigated using Taguchi orthogonal array design. The maximum extraction efficiency of cadmium ions was obtained at pH = 8, sorbent weight = 0.1 g, ionic strength = 0, stirring time = 15 min, sample volume = 100 mL, time of desorption = 5 min, concentration and volume of HCl solution as desorption solvent 0.1 M and 3 mL, respectively. The linear dynamic range, limit of detection, enhancement factor and relative standard deviation (RSD %) of the proposed method were obtained as 0.5–100 µg L⁻¹ (R² = 0.9982), 0.4 µg L⁻¹, 26.9 and 3.5%, respectively. Finally, the study of proposed MMNC adsorbent for real sample and investigating the interference potential of foreign ions successfully confirmed the ability of MMNCs for preconcentration and determination of trace levels of cadmium ions.

在这项研究中，已经开发了一种简单而灵敏的萃取方法，该方法使用固溶有磺酸基团的Kit-6磁铁矿介孔纳米复合材料（MMNC）作为吸附剂进行固相萃取，然后进行火焰原子吸收光谱法预富集痕量镉离子。为此，在涂有二氧化硅的磁铁矿芯表面化学合成了Kit-6介孔二氧化硅，并通过磺酸基团对其进行了官能化处理，从而获得了Fe ₃ O ₄ @SiO ₂ @ Kit-6-SO _3。H.通过XRD，SEM，VSM和EDX方法对合成的纳米复合材料进行了表征。使用Taguchi正交阵列设计研究了影响吸附/解吸效率的各种参数。在pH = 8，吸附剂重量= 0.1 g，离子强度= 0，搅拌时间= 15分钟，样品量= 100 mL，解吸时间= 5分钟，HCl溶液的浓度和体积的条件下，可获得最大的镉离子萃取效率。作为解吸溶剂，分别为0.1 M和3 mL。该方法的线性动态范围，检出限，增强因子和相对标准偏差（RSD％）为0.5–100 µg L ^-1（R ²  = 0.9982），0.4 µg L ^-1，分别为26.9和3.5％。最后，对所提出的用于实际样品的MMNC吸附剂的研究以及对外来离子的干扰潜能的研究成功地证实了MMNCs能够进行预富集和测定痕量镉离子的能力。